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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Soon after the Chunga-Changa island was discovered, it started to acquire some forms of civilization and even market economy. A new currency arose, colloquially called "chizhik". One has to pay in chizhiks to buy a coconut now. Sasha and Masha are about to buy some coconuts which are sold at price z chizhiks per coconut. Sasha has x chizhiks, Masha has y chizhiks. Each girl will buy as many coconuts as she can using only her money. This way each girl will buy an integer non-negative number of coconuts. The girls discussed their plans and found that the total number of coconuts they buy can increase (or decrease) if one of them gives several chizhiks to the other girl. The chizhiks can't be split in parts, so the girls can only exchange with integer number of chizhiks. Consider the following example. Suppose Sasha has 5 chizhiks, Masha has 4 chizhiks, and the price for one coconut be 3 chizhiks. If the girls don't exchange with chizhiks, they will buy 1 + 1 = 2 coconuts. However, if, for example, Masha gives Sasha one chizhik, then Sasha will have 6 chizhiks, Masha will have 3 chizhiks, and the girls will buy 2 + 1 = 3 coconuts. It is not that easy to live on the island now, so Sasha and Mash want to exchange with chizhiks in such a way that they will buy the maximum possible number of coconuts. Nobody wants to have a debt, so among all possible ways to buy the maximum possible number of coconuts find such a way that minimizes the number of chizhiks one girl gives to the other (it is not important who will be the person giving the chizhiks). Input The first line contains three integers x, y and z (0 ≤ x, y ≤ 10^{18}, 1 ≤ z ≤ 10^{18}) — the number of chizhics Sasha has, the number of chizhics Masha has and the price of a coconut. Output Print two integers: the maximum possible number of coconuts the girls can buy and the minimum number of chizhiks one girl has to give to the other. Examples Input 5 4 3 Output 3 1 Input 6 8 2 Output 7 0 Note The first example is described in the statement. In the second example the optimal solution is to dot exchange any chizhiks. The girls will buy 3 + 4 = 7 coconuts. Submitted Solution: ``` inputs = input().split(' ') x = int(inputs[0]) y = int(inputs[1]) z = int(inputs[2]) exchange = 0 coconuts = 0 small = min(x, y) if x + y % z == 0: coconuts = x + y // z exchange = small % z; else: coconuts = (x + y) // z exchange = small % z print (coconuts, exchange) ``` No
104,500
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Soon after the Chunga-Changa island was discovered, it started to acquire some forms of civilization and even market economy. A new currency arose, colloquially called "chizhik". One has to pay in chizhiks to buy a coconut now. Sasha and Masha are about to buy some coconuts which are sold at price z chizhiks per coconut. Sasha has x chizhiks, Masha has y chizhiks. Each girl will buy as many coconuts as she can using only her money. This way each girl will buy an integer non-negative number of coconuts. The girls discussed their plans and found that the total number of coconuts they buy can increase (or decrease) if one of them gives several chizhiks to the other girl. The chizhiks can't be split in parts, so the girls can only exchange with integer number of chizhiks. Consider the following example. Suppose Sasha has 5 chizhiks, Masha has 4 chizhiks, and the price for one coconut be 3 chizhiks. If the girls don't exchange with chizhiks, they will buy 1 + 1 = 2 coconuts. However, if, for example, Masha gives Sasha one chizhik, then Sasha will have 6 chizhiks, Masha will have 3 chizhiks, and the girls will buy 2 + 1 = 3 coconuts. It is not that easy to live on the island now, so Sasha and Mash want to exchange with chizhiks in such a way that they will buy the maximum possible number of coconuts. Nobody wants to have a debt, so among all possible ways to buy the maximum possible number of coconuts find such a way that minimizes the number of chizhiks one girl gives to the other (it is not important who will be the person giving the chizhiks). Input The first line contains three integers x, y and z (0 ≤ x, y ≤ 10^{18}, 1 ≤ z ≤ 10^{18}) — the number of chizhics Sasha has, the number of chizhics Masha has and the price of a coconut. Output Print two integers: the maximum possible number of coconuts the girls can buy and the minimum number of chizhiks one girl has to give to the other. Examples Input 5 4 3 Output 3 1 Input 6 8 2 Output 7 0 Note The first example is described in the statement. In the second example the optimal solution is to dot exchange any chizhiks. The girls will buy 3 + 4 = 7 coconuts. Submitted Solution: ``` x, y, z = [int(x) for x in input().split(' ')] x1 = x // z y1 = y // z z1 = (x + y) // z if x1 + y1 == z1: print(z1, 0) else: print(z1, min(max(x, z) % min(x, z), max(y, z) % min(y, z))) ``` No
104,501
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Soon after the Chunga-Changa island was discovered, it started to acquire some forms of civilization and even market economy. A new currency arose, colloquially called "chizhik". One has to pay in chizhiks to buy a coconut now. Sasha and Masha are about to buy some coconuts which are sold at price z chizhiks per coconut. Sasha has x chizhiks, Masha has y chizhiks. Each girl will buy as many coconuts as she can using only her money. This way each girl will buy an integer non-negative number of coconuts. The girls discussed their plans and found that the total number of coconuts they buy can increase (or decrease) if one of them gives several chizhiks to the other girl. The chizhiks can't be split in parts, so the girls can only exchange with integer number of chizhiks. Consider the following example. Suppose Sasha has 5 chizhiks, Masha has 4 chizhiks, and the price for one coconut be 3 chizhiks. If the girls don't exchange with chizhiks, they will buy 1 + 1 = 2 coconuts. However, if, for example, Masha gives Sasha one chizhik, then Sasha will have 6 chizhiks, Masha will have 3 chizhiks, and the girls will buy 2 + 1 = 3 coconuts. It is not that easy to live on the island now, so Sasha and Mash want to exchange with chizhiks in such a way that they will buy the maximum possible number of coconuts. Nobody wants to have a debt, so among all possible ways to buy the maximum possible number of coconuts find such a way that minimizes the number of chizhiks one girl gives to the other (it is not important who will be the person giving the chizhiks). Input The first line contains three integers x, y and z (0 ≤ x, y ≤ 10^{18}, 1 ≤ z ≤ 10^{18}) — the number of chizhics Sasha has, the number of chizhics Masha has and the price of a coconut. Output Print two integers: the maximum possible number of coconuts the girls can buy and the minimum number of chizhiks one girl has to give to the other. Examples Input 5 4 3 Output 3 1 Input 6 8 2 Output 7 0 Note The first example is described in the statement. In the second example the optimal solution is to dot exchange any chizhiks. The girls will buy 3 + 4 = 7 coconuts. Submitted Solution: ``` z,c,a=list(map(int,input().split())) if z%a>c%a:print((z+c%a+c-c%a)//a,c%a,end=' ') elif c%a>z%a:print((c+z%a+z-z%a)//a,z%a,end=' ') elif z%a==c%a:print((z+c)//a,0,end=' ') ``` No
104,502
Provide tags and a correct Python 3 solution for this coding contest problem. The only difference between the easy and the hard versions is the maximum value of k. You are given an infinite sequence of form "112123123412345..." which consist of blocks of all consecutive positive integers written one after another. The first block consists of all numbers from 1 to 1, the second one — from 1 to 2, the third one — from 1 to 3, ..., the i-th block consists of all numbers from 1 to i. So the first 56 elements of the sequence are "11212312341234512345612345671234567812345678912345678910". Elements of the sequence are numbered from one. For example, the 1-st element of the sequence is 1, the 3-rd element of the sequence is 2, the 20-th element of the sequence is 5, the 38-th element is 2, the 56-th element of the sequence is 0. Your task is to answer q independent queries. In the i-th query you are given one integer k_i. Calculate the digit at the position k_i of the sequence. Input The first line of the input contains one integer q (1 ≤ q ≤ 500) — the number of queries. The i-th of the following q lines contains one integer k_i (1 ≤ k_i ≤ 10^9) — the description of the corresponding query. Output Print q lines. In the i-th line print one digit x_i (0 ≤ x_i ≤ 9) — the answer to the query i, i.e. x_i should be equal to the element at the position k_i of the sequence. Examples Input 5 1 3 20 38 56 Output 1 2 5 2 0 Input 4 2132 506 999999999 1000000000 Output 8 2 9 8 Note Answers on queries from the first example are described in the problem statement. Tags: binary search, brute force, math Correct Solution: ``` import sys input = sys.stdin.readline # 1keta : 1,2,3,4,5,6,7,8,9 : 45 # 2keta : 11,13,15,... # 9 : 9 , sum = 45 # 99 : 9+(2*90) = 189, sum =((9+2)+(9+2*90))*90//2 +45 = 9045 LIST=[9] for i in range(1,20): LIST.append(LIST[-1]+9*(10**i)*(i+1)) SUM=[45] for i in range(1,19): SUM.append(SUM[-1]+(LIST[i-1]+(i+1)+LIST[i])*9*(10**i)//2) def calc(x): True SUM=[0]+SUM LIST=[0]+LIST LIST2=[0] for i in range(1,20): LIST2.append(10**i-1) q=int(input()) #q=1000 for testcases in range(q): k=int(input()) #k=testcases+1 for i in range(20): if SUM[i]>=k: keta=i break #print(keta) k-=SUM[keta-1] INI=LIST[keta-1]+keta #print(k,INI) OK=0 NG=10**keta while NG>OK+1: mid=(OK+NG)//2 if (INI + INI + keta *(mid - 1)) * mid //2 >= k: NG=mid else: OK=mid k-=(INI + INI + keta *(OK - 1)) * OK //2 #print(k,OK,10**(keta-1)+OK) for i in range(20): if LIST[i]>=k: keta2=i k-=LIST[i-1] break #print(k,keta2) r,q=divmod(k,keta2) #print("!",r,q) if q==0: print(str(LIST2[keta2-1]+r)[-1]) else: print(str(LIST2[keta2-1]+r+1)[q-1]) ```
104,503
Provide tags and a correct Python 3 solution for this coding contest problem. The only difference between the easy and the hard versions is the maximum value of k. You are given an infinite sequence of form "112123123412345..." which consist of blocks of all consecutive positive integers written one after another. The first block consists of all numbers from 1 to 1, the second one — from 1 to 2, the third one — from 1 to 3, ..., the i-th block consists of all numbers from 1 to i. So the first 56 elements of the sequence are "11212312341234512345612345671234567812345678912345678910". Elements of the sequence are numbered from one. For example, the 1-st element of the sequence is 1, the 3-rd element of the sequence is 2, the 20-th element of the sequence is 5, the 38-th element is 2, the 56-th element of the sequence is 0. Your task is to answer q independent queries. In the i-th query you are given one integer k_i. Calculate the digit at the position k_i of the sequence. Input The first line of the input contains one integer q (1 ≤ q ≤ 500) — the number of queries. The i-th of the following q lines contains one integer k_i (1 ≤ k_i ≤ 10^9) — the description of the corresponding query. Output Print q lines. In the i-th line print one digit x_i (0 ≤ x_i ≤ 9) — the answer to the query i, i.e. x_i should be equal to the element at the position k_i of the sequence. Examples Input 5 1 3 20 38 56 Output 1 2 5 2 0 Input 4 2132 506 999999999 1000000000 Output 8 2 9 8 Note Answers on queries from the first example are described in the problem statement. Tags: binary search, brute force, math Correct Solution: ``` def digits_until_block_(n): result = 0 for bas in range(1, 30): minimum = int(10 ** (bas - 1)) maximum = int((10 ** bas) - 1) if n < maximum: maximum = n if maximum < minimum: break result += sum_between(n - maximum + 1, n - minimum + 1) * bas return result def digits_until_(n): if n == 0: return 0 if n == 1: return 1 return digits_until_block_(n) - digits_until_block_(n - 1) def sum_between(x, y): try: assert (x <= y) except AssertionError: print(x, y) return ((x + y) * (y - x + 1)) // 2 def solve(q): left = 1 right = 10000000000 while left < right: mid = (left + right) // 2 if digits_until_block_(mid) < q: left = mid + 1 else: right = mid q = q - digits_until_block_(left - 1) left = 1 right = 10000000000 while left < right: mid = (left + right) // 2 if digits_until_(mid) < q: left = mid + 1 else: right = mid q = q - digits_until_(left - 1) return str(left)[q - 1] q = int(input("")) q_list = [] for _ in range(q): q_list.append(int(input(""))) for query in q_list: print(solve(query)) ```
104,504
Provide tags and a correct Python 3 solution for this coding contest problem. The only difference between the easy and the hard versions is the maximum value of k. You are given an infinite sequence of form "112123123412345..." which consist of blocks of all consecutive positive integers written one after another. The first block consists of all numbers from 1 to 1, the second one — from 1 to 2, the third one — from 1 to 3, ..., the i-th block consists of all numbers from 1 to i. So the first 56 elements of the sequence are "11212312341234512345612345671234567812345678912345678910". Elements of the sequence are numbered from one. For example, the 1-st element of the sequence is 1, the 3-rd element of the sequence is 2, the 20-th element of the sequence is 5, the 38-th element is 2, the 56-th element of the sequence is 0. Your task is to answer q independent queries. In the i-th query you are given one integer k_i. Calculate the digit at the position k_i of the sequence. Input The first line of the input contains one integer q (1 ≤ q ≤ 500) — the number of queries. The i-th of the following q lines contains one integer k_i (1 ≤ k_i ≤ 10^9) — the description of the corresponding query. Output Print q lines. In the i-th line print one digit x_i (0 ≤ x_i ≤ 9) — the answer to the query i, i.e. x_i should be equal to the element at the position k_i of the sequence. Examples Input 5 1 3 20 38 56 Output 1 2 5 2 0 Input 4 2132 506 999999999 1000000000 Output 8 2 9 8 Note Answers on queries from the first example are described in the problem statement. Tags: binary search, brute force, math Correct Solution: ``` def cached(func): _cache = {} def wrapped(*args): nonlocal _cache if args not in _cache: _cache[args] = func(*args) return _cache[args] return wrapped def len_num(l): """Количество чисел длины l""" return 10**l - 10**(l - 1) if l > 0 else 0 @cached def len_sum(l): """Сумма длин всех чисел, длина которых строго меньше чем l""" if l <= 1: return 0 return len_sum(l - 1) + (len_num(l - 1)) * (l - 1) def block_len(block_num): """Длина блока (т. е. строки '1234567891011...str(block_num)'""" l = len(str(block_num)) return len_sum(l) + (block_num - 10 ** (l - 1) + 1) * l def arith_sum(n): return n * (n + 1) // 2 @cached def block_len_sum_(l): """Суммарная длина всех блоков длины меньшей чем l""" if l <= 0: return 0 ln = len_num(l - 1) ls = len_sum(l - 1) return block_len_sum_(l - 1) + ls * ln + arith_sum(ln) * (l - 1) def block_len_sum(block_num): """Суммарная длина всех блоков подряд вплоть до блока block_num Если l = len(str(block_num)) """ l = len(str(block_num)) ls = len_sum(l) ln = block_num - (10 ** (l - 1)) + 1 return block_len_sum_(l) + ls * ln + l * arith_sum(ln) def binary_search(call, val): start = 1 end = 1 while call(end) <= val: end *= 2 result = start while start <= end: mid = (start + end) // 2 if call(mid) <= val: start = mid + 1 result = start else: end = mid - 1 return result cases = int(input()) for _ in range(cases): index = int(input()) - 1 block_num = binary_search(block_len_sum, index) rel_index = index - block_len_sum(block_num - 1) number = binary_search(block_len, rel_index) digit = rel_index - block_len(number - 1) print(str(number)[digit]) ```
104,505
Provide tags and a correct Python 3 solution for this coding contest problem. The only difference between the easy and the hard versions is the maximum value of k. You are given an infinite sequence of form "112123123412345..." which consist of blocks of all consecutive positive integers written one after another. The first block consists of all numbers from 1 to 1, the second one — from 1 to 2, the third one — from 1 to 3, ..., the i-th block consists of all numbers from 1 to i. So the first 56 elements of the sequence are "11212312341234512345612345671234567812345678912345678910". Elements of the sequence are numbered from one. For example, the 1-st element of the sequence is 1, the 3-rd element of the sequence is 2, the 20-th element of the sequence is 5, the 38-th element is 2, the 56-th element of the sequence is 0. Your task is to answer q independent queries. In the i-th query you are given one integer k_i. Calculate the digit at the position k_i of the sequence. Input The first line of the input contains one integer q (1 ≤ q ≤ 500) — the number of queries. The i-th of the following q lines contains one integer k_i (1 ≤ k_i ≤ 10^9) — the description of the corresponding query. Output Print q lines. In the i-th line print one digit x_i (0 ≤ x_i ≤ 9) — the answer to the query i, i.e. x_i should be equal to the element at the position k_i of the sequence. Examples Input 5 1 3 20 38 56 Output 1 2 5 2 0 Input 4 2132 506 999999999 1000000000 Output 8 2 9 8 Note Answers on queries from the first example are described in the problem statement. Tags: binary search, brute force, math Correct Solution: ``` import bisect s = [0] # индекс первой цифры блока n = [1] # длина блока while s[-1] < 1.1 * 10e9: number = len(s) + 1 n.append(n[number - 1 - 1] + len(str(number))) s.append(s[number - 1 - 1] + n[number - 1 - 1]) block = ''.join(str(i) for i in range(1, len(s) + 2)) def solve(element): block_num = bisect.bisect_left(s, element) if s[block_num] > element: block_num -= 1 relative_index = element - s[block_num] return block[relative_index] q = int(input()) for _ in range(q): print(solve(int(input()) - 1)) ```
104,506
Provide tags and a correct Python 3 solution for this coding contest problem. The only difference between the easy and the hard versions is the maximum value of k. You are given an infinite sequence of form "112123123412345..." which consist of blocks of all consecutive positive integers written one after another. The first block consists of all numbers from 1 to 1, the second one — from 1 to 2, the third one — from 1 to 3, ..., the i-th block consists of all numbers from 1 to i. So the first 56 elements of the sequence are "11212312341234512345612345671234567812345678912345678910". Elements of the sequence are numbered from one. For example, the 1-st element of the sequence is 1, the 3-rd element of the sequence is 2, the 20-th element of the sequence is 5, the 38-th element is 2, the 56-th element of the sequence is 0. Your task is to answer q independent queries. In the i-th query you are given one integer k_i. Calculate the digit at the position k_i of the sequence. Input The first line of the input contains one integer q (1 ≤ q ≤ 500) — the number of queries. The i-th of the following q lines contains one integer k_i (1 ≤ k_i ≤ 10^9) — the description of the corresponding query. Output Print q lines. In the i-th line print one digit x_i (0 ≤ x_i ≤ 9) — the answer to the query i, i.e. x_i should be equal to the element at the position k_i of the sequence. Examples Input 5 1 3 20 38 56 Output 1 2 5 2 0 Input 4 2132 506 999999999 1000000000 Output 8 2 9 8 Note Answers on queries from the first example are described in the problem statement. Tags: binary search, brute force, math Correct Solution: ``` def l(n): # length of 112123...1234567891011..n s = 0 for i in range(20): o = 10**i-1 if o > n: break s += (n-o) * (n-o+1) // 2 return s def bs(k): # binary search n so l(n) < k n = 0 for p in range(63,-1,-1): if l(n+2**p) < k: n += 2**p return n def num(n): # return s[n-1] where s = '1234567891011..n' if n<10: return n for i in range(1,19): seglen = i * 9 * 10**(i-1) if n <= seglen: return str(10**(i-1) + (n-1)//i)[(n-1)%i] else: n -= seglen q = int(input()) for _ in range(q): k = int(input()) print(num(k-l(bs(k)))) ```
104,507
Provide tags and a correct Python 3 solution for this coding contest problem. The only difference between the easy and the hard versions is the maximum value of k. You are given an infinite sequence of form "112123123412345..." which consist of blocks of all consecutive positive integers written one after another. The first block consists of all numbers from 1 to 1, the second one — from 1 to 2, the third one — from 1 to 3, ..., the i-th block consists of all numbers from 1 to i. So the first 56 elements of the sequence are "11212312341234512345612345671234567812345678912345678910". Elements of the sequence are numbered from one. For example, the 1-st element of the sequence is 1, the 3-rd element of the sequence is 2, the 20-th element of the sequence is 5, the 38-th element is 2, the 56-th element of the sequence is 0. Your task is to answer q independent queries. In the i-th query you are given one integer k_i. Calculate the digit at the position k_i of the sequence. Input The first line of the input contains one integer q (1 ≤ q ≤ 500) — the number of queries. The i-th of the following q lines contains one integer k_i (1 ≤ k_i ≤ 10^9) — the description of the corresponding query. Output Print q lines. In the i-th line print one digit x_i (0 ≤ x_i ≤ 9) — the answer to the query i, i.e. x_i should be equal to the element at the position k_i of the sequence. Examples Input 5 1 3 20 38 56 Output 1 2 5 2 0 Input 4 2132 506 999999999 1000000000 Output 8 2 9 8 Note Answers on queries from the first example are described in the problem statement. Tags: binary search, brute force, math Correct Solution: ``` q=int(input()) a="" for i in range(1,100000): a+=str(i) b=[] ans=0 n=1 i=1 while ans<10**9: ans+=n n+=len(str(i+1)) i+=1 b.append(ans) #print(b) while q: k=int(input()) for i in range(len(b)): if(k>b[i]): x=1 else: if(i>=1): k-=b[i-1] break print(a[k-1]) q-=1 ```
104,508
Provide tags and a correct Python 3 solution for this coding contest problem. The only difference between the easy and the hard versions is the maximum value of k. You are given an infinite sequence of form "112123123412345..." which consist of blocks of all consecutive positive integers written one after another. The first block consists of all numbers from 1 to 1, the second one — from 1 to 2, the third one — from 1 to 3, ..., the i-th block consists of all numbers from 1 to i. So the first 56 elements of the sequence are "11212312341234512345612345671234567812345678912345678910". Elements of the sequence are numbered from one. For example, the 1-st element of the sequence is 1, the 3-rd element of the sequence is 2, the 20-th element of the sequence is 5, the 38-th element is 2, the 56-th element of the sequence is 0. Your task is to answer q independent queries. In the i-th query you are given one integer k_i. Calculate the digit at the position k_i of the sequence. Input The first line of the input contains one integer q (1 ≤ q ≤ 500) — the number of queries. The i-th of the following q lines contains one integer k_i (1 ≤ k_i ≤ 10^9) — the description of the corresponding query. Output Print q lines. In the i-th line print one digit x_i (0 ≤ x_i ≤ 9) — the answer to the query i, i.e. x_i should be equal to the element at the position k_i of the sequence. Examples Input 5 1 3 20 38 56 Output 1 2 5 2 0 Input 4 2132 506 999999999 1000000000 Output 8 2 9 8 Note Answers on queries from the first example are described in the problem statement. Tags: binary search, brute force, math Correct Solution: ``` def isqrt(x): if x < 0: raise ValueError('square root not defined for negative numbers') n = int(x) if n == 0: return 0 a, b = divmod(n.bit_length(), 2) x = 2**(a+b) while True: y = (x + n//x)//2 if y >= x: return x x = y p = [0, 45, 9045, 1395495, 189414495, 23939649495, 2893942449495, 339393974949495, 38939394344949495, 1000000000000000001]; nx = [0, 9, 189, 2889, 38889, 488889, 5888889, 68888889, 788888889, 8888888889] q = int(input()) for ut in range(q): lk = int(input()) k = lk idx = 0; for i in range(len(p)-1): if (p[i] <= k) and (p[i + 1] > k): idx = i; idx = idx; k-=1 k -= p[idx]; a = idx + 1 b = 2 * nx[idx] + idx + 1; k = -2 * k; d = isqrt(b*b-4 * a*k); x1 = (-b + d) / (2. * a); x2 = (-b - d) / (2. * a); a1 = int(x1); z = lk - p[idx] - nx[idx] * a1 - (a1 * (a1 + 1) // 2) * (idx + 1); cnt = 0 ww = 1 pow = 0; pow = 1; while ((cnt + pow * ww) * 9 < z) : cnt += pow * ww; ww+=1 pow *= 10; sym_cnt = (z - (cnt * 9)) - 1; ok = (pow)+sym_cnt / ww; s = str(ok); if (z < 10): print(z) else: print(s[sym_cnt % ww]) ```
104,509
Provide tags and a correct Python 3 solution for this coding contest problem. The only difference between the easy and the hard versions is the maximum value of k. You are given an infinite sequence of form "112123123412345..." which consist of blocks of all consecutive positive integers written one after another. The first block consists of all numbers from 1 to 1, the second one — from 1 to 2, the third one — from 1 to 3, ..., the i-th block consists of all numbers from 1 to i. So the first 56 elements of the sequence are "11212312341234512345612345671234567812345678912345678910". Elements of the sequence are numbered from one. For example, the 1-st element of the sequence is 1, the 3-rd element of the sequence is 2, the 20-th element of the sequence is 5, the 38-th element is 2, the 56-th element of the sequence is 0. Your task is to answer q independent queries. In the i-th query you are given one integer k_i. Calculate the digit at the position k_i of the sequence. Input The first line of the input contains one integer q (1 ≤ q ≤ 500) — the number of queries. The i-th of the following q lines contains one integer k_i (1 ≤ k_i ≤ 10^9) — the description of the corresponding query. Output Print q lines. In the i-th line print one digit x_i (0 ≤ x_i ≤ 9) — the answer to the query i, i.e. x_i should be equal to the element at the position k_i of the sequence. Examples Input 5 1 3 20 38 56 Output 1 2 5 2 0 Input 4 2132 506 999999999 1000000000 Output 8 2 9 8 Note Answers on queries from the first example are described in the problem statement. Tags: binary search, brute force, math Correct Solution: ``` dp, cnt = [0], 1 dp2 = [0] while dp[-1] <= int(1e18): ans = dp2[-1] + (10 ** cnt - 10 ** (cnt - 1)) * cnt dp2.append(ans) ans = dp[-1] + dp2[-2] * (10 ** cnt - 10 ** (cnt - 1)) + cnt * (10 ** cnt - 10 ** (cnt - 1) + 1) * (10 ** cnt - 10 ** (cnt - 1)) / 2 ans = int(ans) cnt += 1 dp.append(ans) def Cal(a, b): return dp2[b - 1] * a + b * int(a * (a + 1) / 2) q = int(input()) for _ in range(q): k = int(input()) i = 0 while k > dp[i]: i += 1 k -= dp[i - 1] l, r = 0, 10 ** i - 10 ** (i - 1) last = int((l + r) / 2) while not(Cal(last, i) < k and Cal(last + 1, i) >= k): if(Cal(last, i) < k): l = last last = int((l + r) / 2 + 1) else: r = last last = int((l + r) / 2) k -= Cal(last, i) j = 0 while dp2[j] < k: j += 1 k -= dp2[j - 1] a = int((k - 1) / j) k -= a * j Long = str(10 ** (j - 1) + a) print(Long[k - 1]) ```
104,510
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. The only difference between the easy and the hard versions is the maximum value of k. You are given an infinite sequence of form "112123123412345..." which consist of blocks of all consecutive positive integers written one after another. The first block consists of all numbers from 1 to 1, the second one — from 1 to 2, the third one — from 1 to 3, ..., the i-th block consists of all numbers from 1 to i. So the first 56 elements of the sequence are "11212312341234512345612345671234567812345678912345678910". Elements of the sequence are numbered from one. For example, the 1-st element of the sequence is 1, the 3-rd element of the sequence is 2, the 20-th element of the sequence is 5, the 38-th element is 2, the 56-th element of the sequence is 0. Your task is to answer q independent queries. In the i-th query you are given one integer k_i. Calculate the digit at the position k_i of the sequence. Input The first line of the input contains one integer q (1 ≤ q ≤ 500) — the number of queries. The i-th of the following q lines contains one integer k_i (1 ≤ k_i ≤ 10^9) — the description of the corresponding query. Output Print q lines. In the i-th line print one digit x_i (0 ≤ x_i ≤ 9) — the answer to the query i, i.e. x_i should be equal to the element at the position k_i of the sequence. Examples Input 5 1 3 20 38 56 Output 1 2 5 2 0 Input 4 2132 506 999999999 1000000000 Output 8 2 9 8 Note Answers on queries from the first example are described in the problem statement. Submitted Solution: ``` import sys input = sys.stdin.readline print = sys.stdout.write for _ in range(int(input())): k = int(input()) k -= 1 n = 0 m = 0 while k >= m: k -= m n += 1 m += len(str(n)) i = 1 while k >= len(str(i)): k -= len(str(i)) i += 1 print(str(i)[k] + '\n') ``` Yes
104,511
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. The only difference between the easy and the hard versions is the maximum value of k. You are given an infinite sequence of form "112123123412345..." which consist of blocks of all consecutive positive integers written one after another. The first block consists of all numbers from 1 to 1, the second one — from 1 to 2, the third one — from 1 to 3, ..., the i-th block consists of all numbers from 1 to i. So the first 56 elements of the sequence are "11212312341234512345612345671234567812345678912345678910". Elements of the sequence are numbered from one. For example, the 1-st element of the sequence is 1, the 3-rd element of the sequence is 2, the 20-th element of the sequence is 5, the 38-th element is 2, the 56-th element of the sequence is 0. Your task is to answer q independent queries. In the i-th query you are given one integer k_i. Calculate the digit at the position k_i of the sequence. Input The first line of the input contains one integer q (1 ≤ q ≤ 500) — the number of queries. The i-th of the following q lines contains one integer k_i (1 ≤ k_i ≤ 10^9) — the description of the corresponding query. Output Print q lines. In the i-th line print one digit x_i (0 ≤ x_i ≤ 9) — the answer to the query i, i.e. x_i should be equal to the element at the position k_i of the sequence. Examples Input 5 1 3 20 38 56 Output 1 2 5 2 0 Input 4 2132 506 999999999 1000000000 Output 8 2 9 8 Note Answers on queries from the first example are described in the problem statement. Submitted Solution: ``` class Num: cur, digits, di = 0, 0, {} def dig(n): if "1"+"0"*(len(str(n))-1)==str(n): Num.cur += 1 Num.digits += Num.cur else: Num.digits += Num.cur return Num.digits def work(n): j=n start = 1 Num.cur, Num.digits=0,0 done = False while not done: next = dig(start) if n > next: n -= next start += 1 else: done=True p=1 while n > 9*p*(10**(p-1)): n -= 9*p*(10**(p-1)) p += 1 starts = 10**(p-1) if n <= p: Num.di[j] = str(starts)[n-1] else: cv = int(n/p) starts += cv n -= cv*p if n==0: Num.di[j] = str(starts-1)[-1] else: Num.di[j] = str(starts)[n-1] q = int(input()) li = [] for i in range(q): li.append(int(input())) for j in sorted(li): work(j) for j in li: print(Num.di[j]) ``` Yes
104,512
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. The only difference between the easy and the hard versions is the maximum value of k. You are given an infinite sequence of form "112123123412345..." which consist of blocks of all consecutive positive integers written one after another. The first block consists of all numbers from 1 to 1, the second one — from 1 to 2, the third one — from 1 to 3, ..., the i-th block consists of all numbers from 1 to i. So the first 56 elements of the sequence are "11212312341234512345612345671234567812345678912345678910". Elements of the sequence are numbered from one. For example, the 1-st element of the sequence is 1, the 3-rd element of the sequence is 2, the 20-th element of the sequence is 5, the 38-th element is 2, the 56-th element of the sequence is 0. Your task is to answer q independent queries. In the i-th query you are given one integer k_i. Calculate the digit at the position k_i of the sequence. Input The first line of the input contains one integer q (1 ≤ q ≤ 500) — the number of queries. The i-th of the following q lines contains one integer k_i (1 ≤ k_i ≤ 10^9) — the description of the corresponding query. Output Print q lines. In the i-th line print one digit x_i (0 ≤ x_i ≤ 9) — the answer to the query i, i.e. x_i should be equal to the element at the position k_i of the sequence. Examples Input 5 1 3 20 38 56 Output 1 2 5 2 0 Input 4 2132 506 999999999 1000000000 Output 8 2 9 8 Note Answers on queries from the first example are described in the problem statement. Submitted Solution: ``` import io import os import collections import math import functools import itertools import bisect import heapq from sys import stdin, stdout, stderr from collections import * from math import * from functools import * from itertools import * from heapq import * from bisect import bisect_left, bisect_right, insort_left, insort_right input = io.BytesIO(os.read(0, os.fstat(0).st_size)).readline def get_ints(): return list(map(int, input().split())) def get_int(): return int(input()) def get_str(): return "".join(list(map(chr, input()))[:-1]) def eprint(*args): stderr.write(", ".join(map(str, args)) + "\n") def print(*args): stdout.write(" ".join(map(str, args)) + "\n") # **************************************************************************** # q = get_int() arr = [get_int() for _ in range(q)] arr = [(x, i) for i, x in enumerate(arr)] arr.sort() res = [0] * q strs = [] s_ps = [0] t_ps = [0] s_len = 0 t_len = 0 x = 0 ''' 1 112 1 12 123 1234 12345 123456 1234567 12345678 123456789 12345678910 11212312341234512345612345671234567812345678912345678910 ''' for n, i in arr: while t_len < n: x += 1 xs = str(x) strs.append(xs) s_len += len(xs) s_ps.append(s_len) t_len += s_len t_ps.append(t_len) nn = n - t_ps[-2] si = bisect_left(s_ps, nn) - 1 ss = strs[si] if si < len(strs) else None sci = nn - s_ps[si] - 1 sc = ss[sci] #eprint(n, nn, i, strs, s_ps, t_ps, x, si, ss, sci, sc) res[i] = sc for r in res: print(r) ``` Yes
104,513
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. The only difference between the easy and the hard versions is the maximum value of k. You are given an infinite sequence of form "112123123412345..." which consist of blocks of all consecutive positive integers written one after another. The first block consists of all numbers from 1 to 1, the second one — from 1 to 2, the third one — from 1 to 3, ..., the i-th block consists of all numbers from 1 to i. So the first 56 elements of the sequence are "11212312341234512345612345671234567812345678912345678910". Elements of the sequence are numbered from one. For example, the 1-st element of the sequence is 1, the 3-rd element of the sequence is 2, the 20-th element of the sequence is 5, the 38-th element is 2, the 56-th element of the sequence is 0. Your task is to answer q independent queries. In the i-th query you are given one integer k_i. Calculate the digit at the position k_i of the sequence. Input The first line of the input contains one integer q (1 ≤ q ≤ 500) — the number of queries. The i-th of the following q lines contains one integer k_i (1 ≤ k_i ≤ 10^9) — the description of the corresponding query. Output Print q lines. In the i-th line print one digit x_i (0 ≤ x_i ≤ 9) — the answer to the query i, i.e. x_i should be equal to the element at the position k_i of the sequence. Examples Input 5 1 3 20 38 56 Output 1 2 5 2 0 Input 4 2132 506 999999999 1000000000 Output 8 2 9 8 Note Answers on queries from the first example are described in the problem statement. Submitted Solution: ``` q = int(input()) for _ in range(q): k = int(input()) if k == 933939799: print(7) else: d = 1 l = 0 n = 9 a1 = 1 while l + (2*a1 + (n-1)*d) * n // 2 < k: l += (2*a1 + (n-1)*d) * n // 2 a1 += (n * d + 1) d += 1 n *= 10 k -= l while k - a1 > 0: k -= a1 a1 += d n = 9 d = 1 l = 0 while l + n * d < k: l += n * d d += 1 n *= 10 k -= l l = 0 s = '' start = int('1' + '0'*(d-1)) n = 1 while k - d * start > 0: k -= d * start n += 1 n = int(str(n) + '0'*(d-1)) while l < k: s += str(n) l += len(str(n)) n += 1 print(s[k-1]) ``` Yes
104,514
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. The only difference between the easy and the hard versions is the maximum value of k. You are given an infinite sequence of form "112123123412345..." which consist of blocks of all consecutive positive integers written one after another. The first block consists of all numbers from 1 to 1, the second one — from 1 to 2, the third one — from 1 to 3, ..., the i-th block consists of all numbers from 1 to i. So the first 56 elements of the sequence are "11212312341234512345612345671234567812345678912345678910". Elements of the sequence are numbered from one. For example, the 1-st element of the sequence is 1, the 3-rd element of the sequence is 2, the 20-th element of the sequence is 5, the 38-th element is 2, the 56-th element of the sequence is 0. Your task is to answer q independent queries. In the i-th query you are given one integer k_i. Calculate the digit at the position k_i of the sequence. Input The first line of the input contains one integer q (1 ≤ q ≤ 500) — the number of queries. The i-th of the following q lines contains one integer k_i (1 ≤ k_i ≤ 10^9) — the description of the corresponding query. Output Print q lines. In the i-th line print one digit x_i (0 ≤ x_i ≤ 9) — the answer to the query i, i.e. x_i should be equal to the element at the position k_i of the sequence. Examples Input 5 1 3 20 38 56 Output 1 2 5 2 0 Input 4 2132 506 999999999 1000000000 Output 8 2 9 8 Note Answers on queries from the first example are described in the problem statement. Submitted Solution: ``` from collections import deque import sys import math import bisect def inp(): return sys.stdin.readline().strip() def f(i): if i==1: return 1 logi=math.floor(math.log(i,10))+1 val=(logi-1)*(10**(logi-1))-((10**(logi-1)-1)//9)+i*logi-((10**(logi-1)) -1)*logi return int(val) precompute=[0] i=1 while precompute[-1]<10**10: precompute.append(precompute[i-1]+f(i)) i+=1 for _ in range(int(inp())): k=int(inp()) j=bisect.bisect_right(precompute,k) tbf=k-precompute[j-1] if tbf==0: print((j-1)%10) continue l=1 r=int(1e10) ans=1 while l<=r: m=(l+r)//2 if f(m)<=tbf: ans=int(m) l=m+1 else: r=m-1 diff=tbf-f(ans) m=ans st='' while len(st)<=diff: st=str(m)+st m-=1 #print(st) back=int(tbf-f(ans))-1 #print(back) print(st[back]) ``` No
104,515
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. The only difference between the easy and the hard versions is the maximum value of k. You are given an infinite sequence of form "112123123412345..." which consist of blocks of all consecutive positive integers written one after another. The first block consists of all numbers from 1 to 1, the second one — from 1 to 2, the third one — from 1 to 3, ..., the i-th block consists of all numbers from 1 to i. So the first 56 elements of the sequence are "11212312341234512345612345671234567812345678912345678910". Elements of the sequence are numbered from one. For example, the 1-st element of the sequence is 1, the 3-rd element of the sequence is 2, the 20-th element of the sequence is 5, the 38-th element is 2, the 56-th element of the sequence is 0. Your task is to answer q independent queries. In the i-th query you are given one integer k_i. Calculate the digit at the position k_i of the sequence. Input The first line of the input contains one integer q (1 ≤ q ≤ 500) — the number of queries. The i-th of the following q lines contains one integer k_i (1 ≤ k_i ≤ 10^9) — the description of the corresponding query. Output Print q lines. In the i-th line print one digit x_i (0 ≤ x_i ≤ 9) — the answer to the query i, i.e. x_i should be equal to the element at the position k_i of the sequence. Examples Input 5 1 3 20 38 56 Output 1 2 5 2 0 Input 4 2132 506 999999999 1000000000 Output 8 2 9 8 Note Answers on queries from the first example are described in the problem statement. Submitted Solution: ``` num_queries = int(input()) queries = [] for i in range(num_queries): queries.append(int(input())) mq = max(queries) seq = "" i = 1 while len(seq) < mq: stt = "" for j in range(1, i + 1): stt = stt + str(j) seq = seq + stt i = i + 1 print(seq) for query in queries: print(seq[query - 1]) ``` No
104,516
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. The only difference between the easy and the hard versions is the maximum value of k. You are given an infinite sequence of form "112123123412345..." which consist of blocks of all consecutive positive integers written one after another. The first block consists of all numbers from 1 to 1, the second one — from 1 to 2, the third one — from 1 to 3, ..., the i-th block consists of all numbers from 1 to i. So the first 56 elements of the sequence are "11212312341234512345612345671234567812345678912345678910". Elements of the sequence are numbered from one. For example, the 1-st element of the sequence is 1, the 3-rd element of the sequence is 2, the 20-th element of the sequence is 5, the 38-th element is 2, the 56-th element of the sequence is 0. Your task is to answer q independent queries. In the i-th query you are given one integer k_i. Calculate the digit at the position k_i of the sequence. Input The first line of the input contains one integer q (1 ≤ q ≤ 500) — the number of queries. The i-th of the following q lines contains one integer k_i (1 ≤ k_i ≤ 10^9) — the description of the corresponding query. Output Print q lines. In the i-th line print one digit x_i (0 ≤ x_i ≤ 9) — the answer to the query i, i.e. x_i should be equal to the element at the position k_i of the sequence. Examples Input 5 1 3 20 38 56 Output 1 2 5 2 0 Input 4 2132 506 999999999 1000000000 Output 8 2 9 8 Note Answers on queries from the first example are described in the problem statement. Submitted Solution: ``` import time q = int(input()) for i in range(q): k=int(input()) y=1 group_l="" full_l=0 start_time=time.time() while 1: group_l+=str(y) if full_l+len(group_l)<k: full_l+=len(group_l) y+=1 else: break med_time=time.time() print("t2-t1=",med_time-start_time) k-=full_l print(group_l[k-1]) end_time=time.time() print("t3-t2=",end_time-med_time) ``` No
104,517
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. The only difference between the easy and the hard versions is the maximum value of k. You are given an infinite sequence of form "112123123412345..." which consist of blocks of all consecutive positive integers written one after another. The first block consists of all numbers from 1 to 1, the second one — from 1 to 2, the third one — from 1 to 3, ..., the i-th block consists of all numbers from 1 to i. So the first 56 elements of the sequence are "11212312341234512345612345671234567812345678912345678910". Elements of the sequence are numbered from one. For example, the 1-st element of the sequence is 1, the 3-rd element of the sequence is 2, the 20-th element of the sequence is 5, the 38-th element is 2, the 56-th element of the sequence is 0. Your task is to answer q independent queries. In the i-th query you are given one integer k_i. Calculate the digit at the position k_i of the sequence. Input The first line of the input contains one integer q (1 ≤ q ≤ 500) — the number of queries. The i-th of the following q lines contains one integer k_i (1 ≤ k_i ≤ 10^9) — the description of the corresponding query. Output Print q lines. In the i-th line print one digit x_i (0 ≤ x_i ≤ 9) — the answer to the query i, i.e. x_i should be equal to the element at the position k_i of the sequence. Examples Input 5 1 3 20 38 56 Output 1 2 5 2 0 Input 4 2132 506 999999999 1000000000 Output 8 2 9 8 Note Answers on queries from the first example are described in the problem statement. Submitted Solution: ``` q=int(input()) s='' l=[0]*25001 for i in range(1,25000): s+=str(i) l[i]=len(s) for i in range(q): k=int(input()) n=1 t=2*k while n*(n+1)<t: n+=1 k-=1 for i in range(1,n+2): if k>l[i]: k-=l[i] else: print(s[k]) break ``` No
104,518
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. I'm the Map, I'm the Map! I'm the MAP!!! Map In anticipation of new adventures Boots wanted to do a good deed. After discussion with the Map and Backpack, they decided to gift Dora a connected graph. After a long search, Boots chose t graph's variants, which Dora might like. However fox Swiper wants to spoil his plan. The Swiper knows, that Dora now is only able to count up to 3, so he has came up with a following idea. He wants to steal some non-empty set of vertices, so that the Dora won't notice the loss. He has decided to steal some non-empty set of vertices, so that after deletion of the stolen vertices and edges adjacent to them, every remaining vertex wouldn't change it's degree modulo 3. The degree of a vertex is the number of edges it is adjacent to. It would've been suspicious to steal all the vertices, so Swiper needs another plan. Boots are sure, that the crime can not be allowed. However they are afraid, that they won't be able to handle this alone. So Boots decided to ask for your help. Please determine for every graph's variant whether the Swiper can perform the theft or not. Input The first line contains a single integer t (1 ≤ t ≤ 100 000) — the number of graph variants. The first line of each variant contains integers n, m (1 ≤ n ≤ 500 000, 0 ≤ m ≤ 500 000), the number of vertexes and edges in the graph. Then m lines follow, each containing integers a_i, b_i (1 ≤ a_i, b_i ≤ n), the indices of the vertices connected with a corresponding edge. It's guaranteed, that the graph is connected and doesn't contain multiple edges or self-loops. It's guaranteed, that the sum of n over all variants is at most 500 000 and that the sum of m over all variants is at most 500 000. Descriptions of graph's variants are separated with an empty line. Output For each variant: * In case the answer exists, print "Yes" and then the answer itself. The first line should contain an integer c (1 < c < n), the number of vertices the Crook can steal, without Dora noticing the loss. On the next line print c distinct integers, the indices of the graph's vertices in arbitrary order. * Otherwise print "No". In case there are several correct ways to steal the vertices, print any of them. Please note, that it's not required to maximize the number of stolen vertices. Example Input 3 3 3 1 2 2 3 3 1 6 6 1 2 1 3 2 3 2 5 2 6 2 4 8 12 1 2 1 3 2 3 1 4 4 5 5 1 3 6 3 7 3 8 6 1 7 1 8 1 Output No Yes 3 4 5 6 Yes 3 6 7 8 Note The picture below shows the third variant from the example test. The set of the vertices the Crook can steal is denoted with bold. <image> Submitted Solution: ``` from collections import deque from typing import List N = 500005 visited = [False] * N good = [False] * N parent = [0] * N h = [0] * N adj: List[List[int]] = [[] for _ in range(N)] q = deque() degree = [0] * N def dfs1(u: int): mx = -1 visited[u] = True for v in adj[u]: if visited[v] and h[v] < h[u] - 1 and (mx == -1 or h[v] > h[mx]): mx = v if mx != -1 and h[u] - h[mx] + 1 < n and degree[mx] % 3 > 1: while u != parent[mx]: good[u] = True u = parent[u] return True for v in adj[u]: if not visited[v]: parent[v] = u h[v] = h[u] + 1 if dfs1(v): return True return False def dfs2(u: int): visited[u] = True for v in adj[u]: if not visited[v]: dfs2(v) def has_3k_vertex(): for i in range(n): if degree[i] % 3 == 0: good[i] = True return True return False def has_121_path(): parent[root] = -1 visited[root] = True q.append(root) while len(q): u = q.popleft() if u != root and degree[u] % 3 == 1 and h[u] < n - 1: while u != -1: good[u] = True u = parent[u] q.clear() return True for v in adj[u]: if not visited[v]: visited[v] = True q.append(v) parent[v] = u h[v] = h[u] + 1 q.popleft() def has_2_cycle(): parent[root if root < n else 0] = -1 for i in range(n): visited[i] = False return dfs1(root if root < n else 0) def has_122_components(): flag = False for i in range(n): visited[i] = False visited[root] = good[root] = True # adj[root].sort(key=lambda a: h[a]) for u in adj[root]: if not visited[u] and h[u] > 1: v = u good[u] = True while parent[v] != root: v = parent[v] good[v] = True if flag: break dfs2(v) flag = True return True if __name__ == '__main__': s = int(input()) while s > 0: n, m = [int(a) for a in input().split(' ')] for i in range(m): u, v = [int(a) - 1 for a in input().split(' ')] degree[u] += 1 degree[v] += 1 adj[u].append(v) adj[v].append(u) v1 = [a for a in range(n) if degree[a] % 3 == 1] root = v1[0] if len(v1) > 0 else n if has_3k_vertex() or (len(v1) > 1 and has_121_path()) or has_2_cycle() or\ (root < n and degree[root] > 4 and has_122_components()): li = list() for i in range(n): if not good[i]: li.append(str(i + 1)) print("Yes") print(len(li)) print(' '.join(li)) else: print('No') for i in range(n): adj[i].clear() visited[i] = good[i] = False parent[i] = degree[i] = h[i] = 0 s -= 1 if s != 0: input() ``` No
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. I'm the Map, I'm the Map! I'm the MAP!!! Map In anticipation of new adventures Boots wanted to do a good deed. After discussion with the Map and Backpack, they decided to gift Dora a connected graph. After a long search, Boots chose t graph's variants, which Dora might like. However fox Swiper wants to spoil his plan. The Swiper knows, that Dora now is only able to count up to 3, so he has came up with a following idea. He wants to steal some non-empty set of vertices, so that the Dora won't notice the loss. He has decided to steal some non-empty set of vertices, so that after deletion of the stolen vertices and edges adjacent to them, every remaining vertex wouldn't change it's degree modulo 3. The degree of a vertex is the number of edges it is adjacent to. It would've been suspicious to steal all the vertices, so Swiper needs another plan. Boots are sure, that the crime can not be allowed. However they are afraid, that they won't be able to handle this alone. So Boots decided to ask for your help. Please determine for every graph's variant whether the Swiper can perform the theft or not. Input The first line contains a single integer t (1 ≤ t ≤ 100 000) — the number of graph variants. The first line of each variant contains integers n, m (1 ≤ n ≤ 500 000, 0 ≤ m ≤ 500 000), the number of vertexes and edges in the graph. Then m lines follow, each containing integers a_i, b_i (1 ≤ a_i, b_i ≤ n), the indices of the vertices connected with a corresponding edge. It's guaranteed, that the graph is connected and doesn't contain multiple edges or self-loops. It's guaranteed, that the sum of n over all variants is at most 500 000 and that the sum of m over all variants is at most 500 000. Descriptions of graph's variants are separated with an empty line. Output For each variant: * In case the answer exists, print "Yes" and then the answer itself. The first line should contain an integer c (1 < c < n), the number of vertices the Crook can steal, without Dora noticing the loss. On the next line print c distinct integers, the indices of the graph's vertices in arbitrary order. * Otherwise print "No". In case there are several correct ways to steal the vertices, print any of them. Please note, that it's not required to maximize the number of stolen vertices. Example Input 3 3 3 1 2 2 3 3 1 6 6 1 2 1 3 2 3 2 5 2 6 2 4 8 12 1 2 1 3 2 3 1 4 4 5 5 1 3 6 3 7 3 8 6 1 7 1 8 1 Output No Yes 3 4 5 6 Yes 3 6 7 8 Note The picture below shows the third variant from the example test. The set of the vertices the Crook can steal is denoted with bold. <image> Submitted Solution: ``` upper,lower,n,m = 0,0,0,0 graph = [] deg = [] depth = [] parent = [] q = [] pred = [] keep = [] mod = [] def dfs(v): global lower global upper r = 0 for u in graph[v]: if parent[v] != u and deg[u] % 3 == 2: if depth[u]: lower = lower if lower else v upper = upper if upper else u r = 1 else: depth[u] = depth[v] + 1 parent[u] = v r |= dfs(u) return r def forest(): r = 1 for v in mod[2]: if depth[v] == 0: parent[v] = -1 depth[v] = 1 if dfs(v): r = 0 return r def answer(): keep.sort() if len(keep) == n: print("No") else: #devolver todos los vértices que van a ser robados, #que sería aquellos que no pertenecen al conjunto keep. print("Yes") print(n - len(keep)) k = n - len(keep) i = 1 j = 0 while k: while i <= n and j < len(keep) and keep[j] == i: i += 1 j += 1 if k == 1: print(i) else: print(i, end=' ') k -= 1 i += 1 def solve(): global n global m global upper global lower for _ in range(m): u,v = map(int,input().split()) graph[u].append(v) graph[v].append(u) deg[u] += 1 deg[v] += 1 for i in range(1,n+1): mod[deg[i]%3].append(i) if n == 1: print("No") elif len(mod[0]) > 0: x = mod[0][0] print("Yes") print(n-1) for i in range(1,n): v = i + 1 if i >= x else i if i + 1 == n: print(v) else: print(v,end=' ') elif not forest(): keep.append(upper) keep.append(lower) #guardar todos los vértices del ciclo i = parent[lower] x = 0 y = 0 print('aqui') while i != upper: keep.append(i) y = depth[i] for v in graph[i]: if y > depth[v] and depth[v] >= depth[upper]: x = v y = depth[v] i = x answer() elif len(mod[1]) == 0: print("No") elif len(mod[1]) >= 2: pred[mod[1][0]] = -1 #cola queue q[0] = mod[1][0] i = 0 j = 1 k = q[0] while i < j: if i and deg[k] % 3 == 1: t = k break for v in graph[k]: if pred[v] == 0: pred[v] = k q[j] = v j += 1 i += 1 k = q[i] #guardar los vértices del camino i = t while ~i: keep.append(i) i = pred[i] answer() else: keep.append(mod[1][0]) fst = graph[mod[1][0]][0] pred[fst] = -1 q[0] = fst last = 0 i = 0 j = 1 k = q[0] while i < j: for v in graph[k]: if pred[v] == 0: if v == mod[1][0]: last = last if (last or (not i) ) else k else: pred[v] = k q[j] = v j += 1 i += 1 k = q[i] #agregar los vértices del primer camino i = last while ~i: keep.append(i) i = pred[i] #encontrar el otro camino for v in graph[mod[1][0]]: if pred[v] == 0: fst = v break last = 0 pred[fst] = -1 q[0] = fst i = 0 j = 1 k = q[0] while i < j: for v in graph[k]: if pred[v] == 0: if v == mod[1][0]: last = last if (last or (not i)) else k else: pred[v] = k q[j] = v j += 1 i += 1 k = q[i] i = last while ~i: keep.append(i) i = pred[i] answer() T = int(input()) for i in range(T): upper = 0 lower = 0 n, m = map(int,input().split()) graph = [[] for _ in range(n + 1)] deg = [0 for _ in range(n + 1)] q = [0 for _ in range(n + 1)] pred = [0 for _ in range(n + 1)] depth = [0 for _ in range(n + 1)] parent = [0 for _ in range(n + 1)] keep = [] mod = [[] for _ in range(3)] solve() if i != T - 1: _ = input() ``` No
104,520
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. I'm the Map, I'm the Map! I'm the MAP!!! Map In anticipation of new adventures Boots wanted to do a good deed. After discussion with the Map and Backpack, they decided to gift Dora a connected graph. After a long search, Boots chose t graph's variants, which Dora might like. However fox Swiper wants to spoil his plan. The Swiper knows, that Dora now is only able to count up to 3, so he has came up with a following idea. He wants to steal some non-empty set of vertices, so that the Dora won't notice the loss. He has decided to steal some non-empty set of vertices, so that after deletion of the stolen vertices and edges adjacent to them, every remaining vertex wouldn't change it's degree modulo 3. The degree of a vertex is the number of edges it is adjacent to. It would've been suspicious to steal all the vertices, so Swiper needs another plan. Boots are sure, that the crime can not be allowed. However they are afraid, that they won't be able to handle this alone. So Boots decided to ask for your help. Please determine for every graph's variant whether the Swiper can perform the theft or not. Input The first line contains a single integer t (1 ≤ t ≤ 100 000) — the number of graph variants. The first line of each variant contains integers n, m (1 ≤ n ≤ 500 000, 0 ≤ m ≤ 500 000), the number of vertexes and edges in the graph. Then m lines follow, each containing integers a_i, b_i (1 ≤ a_i, b_i ≤ n), the indices of the vertices connected with a corresponding edge. It's guaranteed, that the graph is connected and doesn't contain multiple edges or self-loops. It's guaranteed, that the sum of n over all variants is at most 500 000 and that the sum of m over all variants is at most 500 000. Descriptions of graph's variants are separated with an empty line. Output For each variant: * In case the answer exists, print "Yes" and then the answer itself. The first line should contain an integer c (1 < c < n), the number of vertices the Crook can steal, without Dora noticing the loss. On the next line print c distinct integers, the indices of the graph's vertices in arbitrary order. * Otherwise print "No". In case there are several correct ways to steal the vertices, print any of them. Please note, that it's not required to maximize the number of stolen vertices. Example Input 3 3 3 1 2 2 3 3 1 6 6 1 2 1 3 2 3 2 5 2 6 2 4 8 12 1 2 1 3 2 3 1 4 4 5 5 1 3 6 3 7 3 8 6 1 7 1 8 1 Output No Yes 3 4 5 6 Yes 3 6 7 8 Note The picture below shows the third variant from the example test. The set of the vertices the Crook can steal is denoted with bold. <image> Submitted Solution: ``` from typing import List import sys t_p = [] def get_ints(): return map(int, sys.stdin.readline().strip().split()) def puts(string: str): t_p.append(string) def print_solution(solution): for i in solution: can_pick[i] = False to_sol: List[str] = [] for i in range(1, n + 1): if can_pick[i]: to_sol.append(str(i)) if len(to_sol) == 0: puts('No') return puts('Yes') puts(str(len(to_sol))) puts(' '.join(to_sol)) path = [] def nodes_1_22(i): qi: List[int] = [0] * (n + 1) stack = [] stack.append(i) one_time = False while len(stack) > 0: u = stack[-1] if u != i: visited[u] = True else: visited[u] = False if qi[u] >= len(adj[u]): stack.pop() continue v = adj[u][qi[u]] qi[u] += 1 if parent[u] != v: if not visited[v]: if v != i: parent[v] = u stack.append(v) else: visited[v] = True x = u while parent[x] != 0: a = parent[x] if x == i: parent[x] = 0 path.append(x) x = a path.append(x) if one_time: print_solution(path) else: one_time = True def nodes_2(): path = [] qi: List[int] = [0] * (n + 1) stack = [] stack.append(1) while len(stack) > 0: u = stack[-1] visited[u] = True if qi[u] >= len(adj[u]): stack.pop() continue v = adj[u][qi[u]] qi[u] += 1 if parent[u] != v: if not visited[v]: parent[v] = u stack.append(v) else: x = v path.append(x) x = u while x != v: path.append(x) x = parent[x] path.append(x) print_solution(path) return def nodes_1(i): path = [] qi: List[int] = [0] * (n + 1) stack = [] stack.append(i) while len(stack) > 0: u = stack[-1] visited[u] = True if qi[u] == 0: for v in adj[u]: if v != i and len(adj[v]) % 3 == 1: x = u path.append(v) while parent[x] != 0: path.append(x) x = parent[x] path.append(x) print_solution(path) return if qi[u] >= len(adj[u]): stack.pop() continue v = adj[u][qi[u]] qi[u] += 1 if parent[u] != v: if not visited[v]: parent[v] = u if len(adj[v]) % 3 == 1: x = v while parent[x] != 0: path.append(x) x = parent[x] path.append(x) print_solution(path) return stack.append(v) def nodes_0(i): print_solution([i]) def solve(): node_1 = -1 for i in range(1, n + 1): if len(adj[i]) % 3 == 0: nodes_0(i) return for i in range(1, n + 1): if len(adj[i]) % 3 == 1: if node_1 != -1: nodes_1(node_1) return else: node_1 = i if node_1 == -1: nodes_2() else: nodes_1_22(node_1) if __name__ == '__main__': q = int(input()) # input() for qi in range(q): n, m = [int(a) for a in input().split(' ')] adj: List[List[int]] = [[]] + [[] for _ in range(n)] can_pick: List[bool] = [False] + ([True] * n) parent: List[int] = [0] * (n + 1) visited: List[bool] = [False] * (n + 1) for mi in range(m): # input() u, v = [int(a) for a in input().split(' ')] adj[u].append(v) adj[v].append(u) solve() if qi != q - 1: input() sys.stdout.write('\n'.join(t_p)) ``` No
104,521
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. I'm the Map, I'm the Map! I'm the MAP!!! Map In anticipation of new adventures Boots wanted to do a good deed. After discussion with the Map and Backpack, they decided to gift Dora a connected graph. After a long search, Boots chose t graph's variants, which Dora might like. However fox Swiper wants to spoil his plan. The Swiper knows, that Dora now is only able to count up to 3, so he has came up with a following idea. He wants to steal some non-empty set of vertices, so that the Dora won't notice the loss. He has decided to steal some non-empty set of vertices, so that after deletion of the stolen vertices and edges adjacent to them, every remaining vertex wouldn't change it's degree modulo 3. The degree of a vertex is the number of edges it is adjacent to. It would've been suspicious to steal all the vertices, so Swiper needs another plan. Boots are sure, that the crime can not be allowed. However they are afraid, that they won't be able to handle this alone. So Boots decided to ask for your help. Please determine for every graph's variant whether the Swiper can perform the theft or not. Input The first line contains a single integer t (1 ≤ t ≤ 100 000) — the number of graph variants. The first line of each variant contains integers n, m (1 ≤ n ≤ 500 000, 0 ≤ m ≤ 500 000), the number of vertexes and edges in the graph. Then m lines follow, each containing integers a_i, b_i (1 ≤ a_i, b_i ≤ n), the indices of the vertices connected with a corresponding edge. It's guaranteed, that the graph is connected and doesn't contain multiple edges or self-loops. It's guaranteed, that the sum of n over all variants is at most 500 000 and that the sum of m over all variants is at most 500 000. Descriptions of graph's variants are separated with an empty line. Output For each variant: * In case the answer exists, print "Yes" and then the answer itself. The first line should contain an integer c (1 < c < n), the number of vertices the Crook can steal, without Dora noticing the loss. On the next line print c distinct integers, the indices of the graph's vertices in arbitrary order. * Otherwise print "No". In case there are several correct ways to steal the vertices, print any of them. Please note, that it's not required to maximize the number of stolen vertices. Example Input 3 3 3 1 2 2 3 3 1 6 6 1 2 1 3 2 3 2 5 2 6 2 4 8 12 1 2 1 3 2 3 1 4 4 5 5 1 3 6 3 7 3 8 6 1 7 1 8 1 Output No Yes 3 4 5 6 Yes 3 6 7 8 Note The picture below shows the third variant from the example test. The set of the vertices the Crook can steal is denoted with bold. <image> Submitted Solution: ``` from typing import List import sys t_p = [] def get_ints(): return map(int, sys.stdin.readline().strip().split()) def puts(string: str): t_p.append(string) def print_solution(solution): for i in solution: can_pick[i] = False to_sol: List[str] = [] for i in range(1, n + 1): if can_pick[i]: to_sol.append(str(i)) if len(to_sol) == 0: puts('No') return puts('Yes') puts(str(len(to_sol))) puts(' '.join(to_sol)) path = [] def nodes_1_22(i): qi: List[int] = [0] * (n + 1) stack = [] stack.append(i) one_time = False while len(stack) > 0: u = stack[-1] if u != i: visited[u] = True else: visited[u] = False if qi[u] >= len(adj[u]): stack.pop() continue v = adj[u][qi[u]] qi[u] += 1 if parent[u] != v: if not visited[v]: if v != i: parent[v] = u stack.append(v) else: visited[v] = True x = u while parent[x] != 0: a = parent[x] if x == i: parent[x] = 0 path.append(x) x = a path.append(x) if one_time: print_solution(path) else: one_time = True def nodes_2(): path = [] qi: List[int] = [0] * (n + 1) stack = [] stack.append(1) while len(stack) > 0: u = stack[-1] visited[u] = True if qi[u] >= len(adj[u]): stack.pop() continue v = adj[u][qi[u]] qi[u] += 1 if parent[u] != v: if not visited[v]: parent[v] = u stack.append(v) else: x = v path.append(x) x = u while x != v: path.append(x) x = parent[x] path.append(x) print_solution(path) return def nodes_1(i): path = [] qi: List[int] = [0] * (n + 1) stack = [] stack.append(i) while len(stack) > 0: u = stack[-1] visited[u] = True if qi[u] == 0: for v in adj[u]: if v != i and len(adj[v]) % 3 == 1: x = u path.append(v) while parent[x] != 0: path.append(x) x = parent[x] path.append(x) print_solution(path) return if qi[u] >= len(adj[u]): stack.pop() continue v = adj[u][qi[u]] qi[u] += 1 if parent[u] != v: if not visited[v]: parent[v] = u if len(adj[v]) % 3 == 1: x = v while parent[x] != 0: path.append(x) x = parent[x] path.append(x) print_solution(path) return stack.append(v) def nodes_0(i): print_solution([i]) def solve(): node_1 = -1 for i in range(1, n + 1): if len(adj[i]) % 3 == 0: nodes_0(i) return for i in range(1, n + 1): if len(adj[i]) % 3 == 1: if node_1 != -1: nodes_1(node_1) return else: node_1 = i if node_1 == -1: nodes_2() else: nodes_1_22(node_1) if __name__ == '__main__': q = int(input()) # input() i = 0 while i < q: n, m = [int(a) for a in input().split(' ')] if q > 30000 and 159 < i < 160: print(n, m, sep=' ') adj: List[List[int]] = [[]] + [[] for _ in range(n)] can_pick: List[bool] = [False] + ([True] * n) parent: List[int] = [0] * (n + 1) visited: List[bool] = [False] * (n + 1) for mi in range(m): # input() u, v = [int(a) for a in input().split(' ')] adj[u].append(v) adj[v].append(u) if q > 30000 and 159 < i < 160: print(u, v, sep=' ') if q > 30000 and 159 < i < 160: print() if q < 30000: solve() if i != q - 1: input() i += 1 sys.stdout.write('\n'.join(t_p)) ``` No
104,522
Provide tags and a correct Python 3 solution for this coding contest problem. Lengths are measures in Baden in inches and feet. To a length from centimeters it is enough to know that an inch equals three centimeters in Baden and one foot contains 12 inches. You are given a length equal to n centimeters. Your task is to convert it to feet and inches so that the number of feet was maximum. The result should be an integer rounded to the closest value containing an integral number of inches. Note that when you round up, 1 cm rounds up to 0 inches and 2 cm round up to 1 inch. Input The only line contains an integer n (1 ≤ n ≤ 10000). Output Print two non-negative space-separated integers a and b, where a is the numbers of feet and b is the number of inches. Examples Input 42 Output 1 2 Input 5 Output 0 2 Tags: math Correct Solution: ``` n = round(int(input())/3) print(n//12, n%12) ```
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Provide tags and a correct Python 3 solution for this coding contest problem. Lengths are measures in Baden in inches and feet. To a length from centimeters it is enough to know that an inch equals three centimeters in Baden and one foot contains 12 inches. You are given a length equal to n centimeters. Your task is to convert it to feet and inches so that the number of feet was maximum. The result should be an integer rounded to the closest value containing an integral number of inches. Note that when you round up, 1 cm rounds up to 0 inches and 2 cm round up to 1 inch. Input The only line contains an integer n (1 ≤ n ≤ 10000). Output Print two non-negative space-separated integers a and b, where a is the numbers of feet and b is the number of inches. Examples Input 42 Output 1 2 Input 5 Output 0 2 Tags: math Correct Solution: ``` n=int(input()) a = n//3 b = n%3 if b==2: a+=1 s = a//12 y = a%12 print(s,y) ```
104,524
Provide tags and a correct Python 3 solution for this coding contest problem. Lengths are measures in Baden in inches and feet. To a length from centimeters it is enough to know that an inch equals three centimeters in Baden and one foot contains 12 inches. You are given a length equal to n centimeters. Your task is to convert it to feet and inches so that the number of feet was maximum. The result should be an integer rounded to the closest value containing an integral number of inches. Note that when you round up, 1 cm rounds up to 0 inches and 2 cm round up to 1 inch. Input The only line contains an integer n (1 ≤ n ≤ 10000). Output Print two non-negative space-separated integers a and b, where a is the numbers of feet and b is the number of inches. Examples Input 42 Output 1 2 Input 5 Output 0 2 Tags: math Correct Solution: ``` x=(int(input())+1)//3 print(x//12,x%12) ```
104,525
Provide tags and a correct Python 3 solution for this coding contest problem. Lengths are measures in Baden in inches and feet. To a length from centimeters it is enough to know that an inch equals three centimeters in Baden and one foot contains 12 inches. You are given a length equal to n centimeters. Your task is to convert it to feet and inches so that the number of feet was maximum. The result should be an integer rounded to the closest value containing an integral number of inches. Note that when you round up, 1 cm rounds up to 0 inches and 2 cm round up to 1 inch. Input The only line contains an integer n (1 ≤ n ≤ 10000). Output Print two non-negative space-separated integers a and b, where a is the numbers of feet and b is the number of inches. Examples Input 42 Output 1 2 Input 5 Output 0 2 Tags: math Correct Solution: ``` n=int(input()) i=int(n/3)+(n%3)-1 if n%3==0: i+=1 print(i//12," ",i%12) ```
104,526
Provide tags and a correct Python 3 solution for this coding contest problem. Lengths are measures in Baden in inches and feet. To a length from centimeters it is enough to know that an inch equals three centimeters in Baden and one foot contains 12 inches. You are given a length equal to n centimeters. Your task is to convert it to feet and inches so that the number of feet was maximum. The result should be an integer rounded to the closest value containing an integral number of inches. Note that when you round up, 1 cm rounds up to 0 inches and 2 cm round up to 1 inch. Input The only line contains an integer n (1 ≤ n ≤ 10000). Output Print two non-negative space-separated integers a and b, where a is the numbers of feet and b is the number of inches. Examples Input 42 Output 1 2 Input 5 Output 0 2 Tags: math Correct Solution: ``` cm = int(input()) inches = cm // 3 if cm % 3 == 2: inches += 1 feet = inches // 12 inches %= 12 print(feet, inches) ```
104,527
Provide tags and a correct Python 3 solution for this coding contest problem. Lengths are measures in Baden in inches and feet. To a length from centimeters it is enough to know that an inch equals three centimeters in Baden and one foot contains 12 inches. You are given a length equal to n centimeters. Your task is to convert it to feet and inches so that the number of feet was maximum. The result should be an integer rounded to the closest value containing an integral number of inches. Note that when you round up, 1 cm rounds up to 0 inches and 2 cm round up to 1 inch. Input The only line contains an integer n (1 ≤ n ≤ 10000). Output Print two non-negative space-separated integers a and b, where a is the numbers of feet and b is the number of inches. Examples Input 42 Output 1 2 Input 5 Output 0 2 Tags: math Correct Solution: ``` cms=int(input()) al=cms%3 if al==1 or al==0 : ans=cms//3 else: ans=cms//3+1 feet=ans//12 print(feet,ans%12) ```
104,528
Provide tags and a correct Python 3 solution for this coding contest problem. Lengths are measures in Baden in inches and feet. To a length from centimeters it is enough to know that an inch equals three centimeters in Baden and one foot contains 12 inches. You are given a length equal to n centimeters. Your task is to convert it to feet and inches so that the number of feet was maximum. The result should be an integer rounded to the closest value containing an integral number of inches. Note that when you round up, 1 cm rounds up to 0 inches and 2 cm round up to 1 inch. Input The only line contains an integer n (1 ≤ n ≤ 10000). Output Print two non-negative space-separated integers a and b, where a is the numbers of feet and b is the number of inches. Examples Input 42 Output 1 2 Input 5 Output 0 2 Tags: math Correct Solution: ``` n=(int(input())+1)//3 print(n//12,n%12) ```
104,529
Provide tags and a correct Python 3 solution for this coding contest problem. Lengths are measures in Baden in inches and feet. To a length from centimeters it is enough to know that an inch equals three centimeters in Baden and one foot contains 12 inches. You are given a length equal to n centimeters. Your task is to convert it to feet and inches so that the number of feet was maximum. The result should be an integer rounded to the closest value containing an integral number of inches. Note that when you round up, 1 cm rounds up to 0 inches and 2 cm round up to 1 inch. Input The only line contains an integer n (1 ≤ n ≤ 10000). Output Print two non-negative space-separated integers a and b, where a is the numbers of feet and b is the number of inches. Examples Input 42 Output 1 2 Input 5 Output 0 2 Tags: math Correct Solution: ``` n = int(input()) inch = n//3 if n%3 == 2: inch += 1 feet = inch//12 inch = inch%12 print(feet,inch) ```
104,530
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Lengths are measures in Baden in inches and feet. To a length from centimeters it is enough to know that an inch equals three centimeters in Baden and one foot contains 12 inches. You are given a length equal to n centimeters. Your task is to convert it to feet and inches so that the number of feet was maximum. The result should be an integer rounded to the closest value containing an integral number of inches. Note that when you round up, 1 cm rounds up to 0 inches and 2 cm round up to 1 inch. Input The only line contains an integer n (1 ≤ n ≤ 10000). Output Print two non-negative space-separated integers a and b, where a is the numbers of feet and b is the number of inches. Examples Input 42 Output 1 2 Input 5 Output 0 2 Submitted Solution: ``` #------------------------------warmup---------------------------- import os import sys import math from io import BytesIO, IOBase from fractions import Fraction BUFSIZE = 8192 class FastIO(IOBase): newlines = 0 def __init__(self, file): self._fd = file.fileno() self.buffer = BytesIO() self.writable = "x" in file.mode or "r" not in file.mode self.write = self.buffer.write if self.writable else None def read(self): while True: b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE)) if not b: break ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines = 0 return self.buffer.read() def readline(self): while self.newlines == 0: b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE)) self.newlines = b.count(b"\n") + (not b) ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines -= 1 return self.buffer.readline() def flush(self): if self.writable: os.write(self._fd, self.buffer.getvalue()) self.buffer.truncate(0), self.buffer.seek(0) class IOWrapper(IOBase): def __init__(self, file): self.buffer = FastIO(file) self.flush = self.buffer.flush self.writable = self.buffer.writable self.write = lambda s: self.buffer.write(s.encode("ascii")) self.read = lambda: self.buffer.read().decode("ascii") self.readline = lambda: self.buffer.readline().decode("ascii") sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout) input = lambda: sys.stdin.readline().rstrip("\r\n") #-------------------game starts now---------------------------------------------------- n=int(input()) i=n//3 if n%3==2: i+=1 print(i//12,i%12) ``` Yes
104,531
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Lengths are measures in Baden in inches and feet. To a length from centimeters it is enough to know that an inch equals three centimeters in Baden and one foot contains 12 inches. You are given a length equal to n centimeters. Your task is to convert it to feet and inches so that the number of feet was maximum. The result should be an integer rounded to the closest value containing an integral number of inches. Note that when you round up, 1 cm rounds up to 0 inches and 2 cm round up to 1 inch. Input The only line contains an integer n (1 ≤ n ≤ 10000). Output Print two non-negative space-separated integers a and b, where a is the numbers of feet and b is the number of inches. Examples Input 42 Output 1 2 Input 5 Output 0 2 Submitted Solution: ``` from math import ceil, floor n = int(input()) if n % 3 > 1: d = ceil(n / 3) else: d = n // 3 f = d // 12 print(f, d % 12) ``` Yes
104,532
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Lengths are measures in Baden in inches and feet. To a length from centimeters it is enough to know that an inch equals three centimeters in Baden and one foot contains 12 inches. You are given a length equal to n centimeters. Your task is to convert it to feet and inches so that the number of feet was maximum. The result should be an integer rounded to the closest value containing an integral number of inches. Note that when you round up, 1 cm rounds up to 0 inches and 2 cm round up to 1 inch. Input The only line contains an integer n (1 ≤ n ≤ 10000). Output Print two non-negative space-separated integers a and b, where a is the numbers of feet and b is the number of inches. Examples Input 42 Output 1 2 Input 5 Output 0 2 Submitted Solution: ``` n=int(input()) a=n//3 b=n%3 if b==2: a=a+1 p=a//12 q=a%12 print(p,q) ``` Yes
104,533
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Lengths are measures in Baden in inches and feet. To a length from centimeters it is enough to know that an inch equals three centimeters in Baden and one foot contains 12 inches. You are given a length equal to n centimeters. Your task is to convert it to feet and inches so that the number of feet was maximum. The result should be an integer rounded to the closest value containing an integral number of inches. Note that when you round up, 1 cm rounds up to 0 inches and 2 cm round up to 1 inch. Input The only line contains an integer n (1 ≤ n ≤ 10000). Output Print two non-negative space-separated integers a and b, where a is the numbers of feet and b is the number of inches. Examples Input 42 Output 1 2 Input 5 Output 0 2 Submitted Solution: ``` n = int(input())/3 ft = int(n//12) inch = round(n%12) if inch == 12: inch = 0 ft += 1 print(ft, inch) ``` Yes
104,534
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Lengths are measures in Baden in inches and feet. To a length from centimeters it is enough to know that an inch equals three centimeters in Baden and one foot contains 12 inches. You are given a length equal to n centimeters. Your task is to convert it to feet and inches so that the number of feet was maximum. The result should be an integer rounded to the closest value containing an integral number of inches. Note that when you round up, 1 cm rounds up to 0 inches and 2 cm round up to 1 inch. Input The only line contains an integer n (1 ≤ n ≤ 10000). Output Print two non-negative space-separated integers a and b, where a is the numbers of feet and b is the number of inches. Examples Input 42 Output 1 2 Input 5 Output 0 2 Submitted Solution: ``` cm = int(input()) cm += 1 dm = divmod(cm, 36) print(dm[0], end=' ') cm = dm[1] print(round(cm / 3)) ``` No
104,535
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Lengths are measures in Baden in inches and feet. To a length from centimeters it is enough to know that an inch equals three centimeters in Baden and one foot contains 12 inches. You are given a length equal to n centimeters. Your task is to convert it to feet and inches so that the number of feet was maximum. The result should be an integer rounded to the closest value containing an integral number of inches. Note that when you round up, 1 cm rounds up to 0 inches and 2 cm round up to 1 inch. Input The only line contains an integer n (1 ≤ n ≤ 10000). Output Print two non-negative space-separated integers a and b, where a is the numbers of feet and b is the number of inches. Examples Input 42 Output 1 2 Input 5 Output 0 2 Submitted Solution: ``` from math import ceil, floor n = int(input()) d = ceil(n / 3) f = d // 12 print(f, d % 12) ``` No
104,536
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Lengths are measures in Baden in inches and feet. To a length from centimeters it is enough to know that an inch equals three centimeters in Baden and one foot contains 12 inches. You are given a length equal to n centimeters. Your task is to convert it to feet and inches so that the number of feet was maximum. The result should be an integer rounded to the closest value containing an integral number of inches. Note that when you round up, 1 cm rounds up to 0 inches and 2 cm round up to 1 inch. Input The only line contains an integer n (1 ≤ n ≤ 10000). Output Print two non-negative space-separated integers a and b, where a is the numbers of feet and b is the number of inches. Examples Input 42 Output 1 2 Input 5 Output 0 2 Submitted Solution: ``` import random import heapq import math from collections import Counter import sys from fractions import gcd sys.setrecursionlimit(300000) from random import randrange ######################################################################### # O(|m| log(max(m) + max(a))) def chinese_remainder(m, a): ''' m - modulos, a - coefficients (arrays) * m have to be mutually COPRIME * ''' res, prod = 0, 1 for m_i in m: prod *= m_i for m_i, a_i in zip(m, a): p = prod // m_i res += a_i * modinv(p, m_i) * p return res % prod # O(log(a+b)) def egcd(a, b): ''' Extended Euclidian algorithm. ''' if a == 0: return (b, 0, 1) else: g, y, x = egcd(b % a, a) return (g, x - (b // a) * y, y) def modinv(a, m): ''' Finds modular inverse of a modulo m. ''' while a < 0: a += m g, x, y = egcd(a, m) if g != 1: raise Exception('Modular inverse does not exist') else: return x % m ######################################################################### ######################################################################### def pi(n): ''' Returns two arrays pi1, pi2: pi1[i] = pi(i) for i <= sqrt(n) pi2[i] = pi(n // i) for i <= sqrt(n) ''' lim = int(n**0.5) while lim*lim <= n: lim += 1 lim -= 1 pi1, pi2 = [0]*(lim + 1), [0]*(lim + 1) for i in range(1, lim + 1): pi1[i] = i - 1 pi2[i] = n//i - 1 for i in range(2, lim + 1): if pi1[i] == pi1[i - 1]: continue p = pi1[i - 1] for j in range(1, min(n // (i * i), lim) + 1): st = i * j if st <= lim: pi2[j] -= pi2[st] - p else: pi2[j] -= pi1[n // st] - p for j in range(lim, min(lim, i * i - 1), -1): pi1[j] -= pi1[j // i] - p return pi1, pi2 ######################################################################### ######################################################################### def num_of_divisors(n): nd = [0] * (n+1) for i in range(1, n+1): for j in range(i, n+1, i): nd[j] += 1 return nd def sum_of_divisors(n): sd = [0] * (n+1) for i in range(1, n+1): for j in range(i, n+1, i): sd[j] += i return sd ######################################################################### def fast_prime_sieve(n): """ Input n>=6, Returns a list of primes, 2 <= p <= n Taken from: https://stackoverflow.com/questions/2068372/fastest-way-to-list-all-primes-below-n/ """ n += 1 n, correction = n-n%6+6, 2-(n%6>1) sieve = [True] * (n//3) for i in range(1,int(n**0.5)//3+1): if sieve[i]: k=3*i+1|1 sieve[ k*k//3 ::2*k] = [False] * ((n//6-k*k//6-1)//k+1) sieve[k*(k-2*(i&1)+4)//3::2*k] = [False] * ((n//6-k*(k-2*(i&1)+4)//6-1)//k+1) return [2,3] + [3*i+1|1 for i in range(1,n//3-correction) if sieve[i]] ######################################################################### def egcd(a, b): ''' Extended Euclidian algorithm. ''' if a == 0: return (b, 0, 1) else: g, y, x = egcd(b % a, a) # x * a + y * b = g return (g, x - (b // a) * y, y) _gcd = lambda a, b: a+b if a==0 or b==0 else gcd(b, a % b) def gcd(a, b): if a==0 or b == 0: return a+b return gcd(b, a % b) ######################################################################### ''' Modular square root ''' ######################################################################### def legendre_symbol(a, p): ls = pow(a, (p - 1) // 2, p) return -1 if ls == p - 1 else ls def modular_sqrt(a, p): if legendre_symbol(a, p) != 1: return 0 elif a == 0: return 0 elif p == 2: return 0 elif p % 4 == 3: return pow(a, (p + 1) // 4, p) s = p - 1 e = 0 while s % 2 == 0: s //= 2 e += 1 n = 2 while legendre_symbol(n, p) != -1: n += 1 x = pow(a, (s + 1) // 2, p) b = pow(a, s, p) g = pow(n, s, p) r = e while True: t = b m = 0 for m in range(r): if t == 1: break t = pow(t, 2, p) if m == 0: return x gs = pow(g, 2 ** (r - m - 1), p) g = (gs * gs) % p x = (x * gs) % p b = (b * g) % p r = m ######################################################################### ''' Euler"s totient function for a single number ''' ######################################################################### from functools import lru_cache def factorize(n): factorization = set() while n > 1: for i in range(2, n + 1): if n % i == 0: n //= i factorization.add(i) break return factorization @lru_cache(maxsize=None) def phi(n): totient = n for p in factorize(n): totient -= totient//p return totient ######################################################################### ######################################################################### def max_subarray(a): max_so_far = max_ending_here = 0 for el in a: # in case a speed-up is required, change the below max/min to if-else statements. max_ending_here = max(0, max_ending_here + el) max_so_far = max(max_so_far, max_ending_here) return max_so_far ######################################################################### ######################################################################### def maximum_xor(nums): answer = 0 for i in range(31, -1, -1): answer <<= 1 prefixes = {num >> i for num in nums} answer += any(answer^1^p in prefixes for p in prefixes) return answer ######################################################################### ''' Finds longest increasing subsequence in O(n log n) time. ''' ######################################################################### def lis(a): p, m, l = [0]*len(a), [0]*(len(a) + 1), 0 for i in range(len(a)): lo, hi = 1, l while lo <= hi: mid = (lo + hi)//2 if a[m[mid]] < a[i]: lo = mid+1 else: hi = mid-1 p[i], m[lo] = m[lo-1], i if lo > l: l = lo s, k = [], m[l] for i in range(l-1, -1, -1): s.append(a[k]) k = p[k] return s[::-1] ######################################################################### ######################################################################### ######################################################################### def find_kth(arr, k, start=0, end=None): if not end: end = len(arr) -1 pivot_ridx = randrange(start, end) pivot = arr[pivot_ridx] pivot_idx = _partition(arr, start, end, pivot_ridx) if pivot_idx + 1 == k: return pivot elif pivot_idx + 1 > k: return find_kth(arr, k, start, pivot_idx) else: return find_kth(arr, k, pivot_idx, end) def _partition(arr, start, end, pivot_idx): pivot = arr[pivot_idx] arr[end], arr[pivot_idx] = arr[pivot_idx], arr[end] inc_idx = start for i in range(start, end): if arr[i] <= pivot: arr[inc_idx], arr[i] = arr[i], arr[inc_idx] inc_idx += 1 arr[end], arr[inc_idx] = arr[inc_idx], arr[end] return inc_idx ######################################################################### ######################################################################### def count_sort(a): mn, mx = float('inf'), -float('inf') for x in a: if x < mn: mn = x if x > mx: mx = x counter = [0 for _ in range(mx - mn + 1)] for x in a: counter[x - mn] += 1 j = 0 for i in range(mx - mn + 1): a[j:j+counter[i]] = [i + mn]*counter[i] j += counter[i] ######################################################################### ######################################################################### def lcs(a, b): ''' Finds longest common subsequence of arrays a, b. ''' lengths = [[0 for j in range(len(b) + 1)] for i in range(len(a) + 1)] for i, x in enumerate(a): for j, y in enumerate(b): if x == y: lengths[i+1][j+1] = lengths[i][j] + 1 else: lengths[i+1][j+1] = max(lengths[i+1][j], lengths[i][j+1]) result = [] x, y = len(a), len(b) while x != 0 and y != 0: if lengths[x][y] == lengths[x-1][y]: x -= 1 elif lengths[x][y] == lengths[x][y-1]: y -= 1 else: result.append(a[x-1]) x, y = x - 1, y - 1 return result[::-1] ######################################################################### ######################################################################### def is_anagram(str1, str2): return Counter(str1) == Counter(str2) ######################################################################### ######################################################################### def power(x, y, p): res = 1; x = x % p; while (y > 0): if (y & 1): res = (res * x) % p; y = y>>1; x = (x * x) % p; return res; ######################################################################### def miillerTest(d, n): a = 2 + random.randint(1, n - 4); x = power(a, d, n); if (x == 1 or x == n - 1): return True; while (d != n - 1): x = (x * x) % n; d *= 2; if (x == 1): return False; if (x == n - 1): return True; return False; def isPrime( n, k): if (n <= 1 or n == 4): return False; if (n <= 3): return True; d = n - 1; while (d % 2 == 0): d //= 2; for i in range(k): if (miillerTest(d, n) == False): return False; return True; ######################################################################### ######################################################################### def gcd_list(li): return reduce(gcd,li) ''' Finds longest increasing subsequence in O(n log n) time. ''' ######################################################################### def lis(a): p, m, l = [0]*len(a), [0]*(len(a) + 1), 0 for i in range(len(a)): lo, hi = 1, l while lo <= hi: mid = (lo + hi)//2 if a[m[mid]] < a[i]: lo = mid+1 else: hi = mid-1 p[i], m[lo] = m[lo-1], i if lo > l: l = lo s, k = [], m[l] for i in range(l-1, -1, -1): s.append(a[k]) k = p[k] return s[::-1] ######################################################################### # for _ in range(int(input())): # input=open("input.txt","r").readline n=int(input()) e=n//36 f=n%36-1 print(e,int(math.ceil((f/3)))) ``` No
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Lengths are measures in Baden in inches and feet. To a length from centimeters it is enough to know that an inch equals three centimeters in Baden and one foot contains 12 inches. You are given a length equal to n centimeters. Your task is to convert it to feet and inches so that the number of feet was maximum. The result should be an integer rounded to the closest value containing an integral number of inches. Note that when you round up, 1 cm rounds up to 0 inches and 2 cm round up to 1 inch. Input The only line contains an integer n (1 ≤ n ≤ 10000). Output Print two non-negative space-separated integers a and b, where a is the numbers of feet and b is the number of inches. Examples Input 42 Output 1 2 Input 5 Output 0 2 Submitted Solution: ``` s = int(input()) f = 0 i = 0 while s >= 36: s -= 36 f += 1 while s >= 3: s -= 3 i += 1 if s == 2: i += 1 print(f, end= ' ') print(i) ``` No
104,538
Provide tags and a correct Python 3 solution for this coding contest problem. We start with a string s consisting only of the digits 1, 2, or 3. The length of s is denoted by |s|. For each i from 1 to |s|, the i-th character of s is denoted by s_i. There is one cursor. The cursor's location ℓ is denoted by an integer in \{0, …, |s|\}, with the following meaning: * If ℓ = 0, then the cursor is located before the first character of s. * If ℓ = |s|, then the cursor is located right after the last character of s. * If 0 < ℓ < |s|, then the cursor is located between s_ℓ and s_{ℓ+1}. We denote by s_left the string to the left of the cursor and s_right the string to the right of the cursor. We also have a string c, which we call our clipboard, which starts out as empty. There are three types of actions: * The Move action. Move the cursor one step to the right. This increments ℓ once. * The Cut action. Set c ← s_right, then set s ← s_left. * The Paste action. Append the value of c to the end of the string s. Note that this doesn't modify c. The cursor initially starts at ℓ = 0. Then, we perform the following procedure: 1. Perform the Move action once. 2. Perform the Cut action once. 3. Perform the Paste action s_ℓ times. 4. If ℓ = x, stop. Otherwise, return to step 1. You're given the initial string s and the integer x. What is the length of s when the procedure stops? Since this value may be very large, only find it modulo 10^9 + 7. It is guaranteed that ℓ ≤ |s| at any time. Input The first line of input contains a single integer t (1 ≤ t ≤ 1000) denoting the number of test cases. The next lines contain descriptions of the test cases. The first line of each test case contains a single integer x (1 ≤ x ≤ 10^6). The second line of each test case consists of the initial string s (1 ≤ |s| ≤ 500). It is guaranteed, that s consists of the characters "1", "2", "3". It is guaranteed that the sum of x in a single file is at most 10^6. It is guaranteed that in each test case before the procedure will stop it will be true that ℓ ≤ |s| at any time. Output For each test case, output a single line containing a single integer denoting the answer for that test case modulo 10^9 + 7. Example Input 4 5 231 7 2323 6 333 24 133321333 Output 25 1438 1101 686531475 Note Let's illustrate what happens with the first test case. Initially, we have s = 231. Initially, ℓ = 0 and c = \varepsilon (the empty string). The following things happen if we follow the procedure above: * Step 1, Move once: we get ℓ = 1. * Step 2, Cut once: we get s = 2 and c = 31. * Step 3, Paste s_ℓ = 2 times: we get s = 23131. * Step 4: ℓ = 1 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 2. * Step 2, Cut once: we get s = 23 and c = 131. * Step 3, Paste s_ℓ = 3 times: we get s = 23131131131. * Step 4: ℓ = 2 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 3. * Step 2, Cut once: we get s = 231 and c = 31131131. * Step 3, Paste s_ℓ = 1 time: we get s = 23131131131. * Step 4: ℓ = 3 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 4. * Step 2, Cut once: we get s = 2313 and c = 1131131. * Step 3, Paste s_ℓ = 3 times: we get s = 2313113113111311311131131. * Step 4: ℓ = 4 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 5. * Step 2, Cut once: we get s = 23131 and c = 13113111311311131131. * Step 3, Paste s_ℓ = 1 times: we get s = 2313113113111311311131131. * Step 4: ℓ = 5 = x, so we stop. At the end of the procedure, s has length 25. Tags: implementation, math Correct Solution: ``` """ NTC here """ from sys import stdin # import threading # setrecursionlimit(10**6) # threading.stack_size(2**26) def iin(): return int(stdin.readline()) def lin(): return list(map(int, stdin.readline().split())) # range = xrange # input = raw_input md=10**9+7 def main(): t=iin() while t: t-=1 x=iin() s=list(input()) l=len(s) ans=l i=0 while i<x: i+=1 ch=int(s[i-1]) ans=(i+ch*(ans-i))%md if l>=x:continue incr=l ss=[] for _ in range(ch): for j in range(i,l): if incr<ans and incr<x: ss.append(s[j]) incr+=1 else: break l=incr for k in ss:s.append(k) #print(ans, l, s) print(ans%md) main() #threading.Thread(target=main).start() ```
104,539
Provide tags and a correct Python 3 solution for this coding contest problem. We start with a string s consisting only of the digits 1, 2, or 3. The length of s is denoted by |s|. For each i from 1 to |s|, the i-th character of s is denoted by s_i. There is one cursor. The cursor's location ℓ is denoted by an integer in \{0, …, |s|\}, with the following meaning: * If ℓ = 0, then the cursor is located before the first character of s. * If ℓ = |s|, then the cursor is located right after the last character of s. * If 0 < ℓ < |s|, then the cursor is located between s_ℓ and s_{ℓ+1}. We denote by s_left the string to the left of the cursor and s_right the string to the right of the cursor. We also have a string c, which we call our clipboard, which starts out as empty. There are three types of actions: * The Move action. Move the cursor one step to the right. This increments ℓ once. * The Cut action. Set c ← s_right, then set s ← s_left. * The Paste action. Append the value of c to the end of the string s. Note that this doesn't modify c. The cursor initially starts at ℓ = 0. Then, we perform the following procedure: 1. Perform the Move action once. 2. Perform the Cut action once. 3. Perform the Paste action s_ℓ times. 4. If ℓ = x, stop. Otherwise, return to step 1. You're given the initial string s and the integer x. What is the length of s when the procedure stops? Since this value may be very large, only find it modulo 10^9 + 7. It is guaranteed that ℓ ≤ |s| at any time. Input The first line of input contains a single integer t (1 ≤ t ≤ 1000) denoting the number of test cases. The next lines contain descriptions of the test cases. The first line of each test case contains a single integer x (1 ≤ x ≤ 10^6). The second line of each test case consists of the initial string s (1 ≤ |s| ≤ 500). It is guaranteed, that s consists of the characters "1", "2", "3". It is guaranteed that the sum of x in a single file is at most 10^6. It is guaranteed that in each test case before the procedure will stop it will be true that ℓ ≤ |s| at any time. Output For each test case, output a single line containing a single integer denoting the answer for that test case modulo 10^9 + 7. Example Input 4 5 231 7 2323 6 333 24 133321333 Output 25 1438 1101 686531475 Note Let's illustrate what happens with the first test case. Initially, we have s = 231. Initially, ℓ = 0 and c = \varepsilon (the empty string). The following things happen if we follow the procedure above: * Step 1, Move once: we get ℓ = 1. * Step 2, Cut once: we get s = 2 and c = 31. * Step 3, Paste s_ℓ = 2 times: we get s = 23131. * Step 4: ℓ = 1 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 2. * Step 2, Cut once: we get s = 23 and c = 131. * Step 3, Paste s_ℓ = 3 times: we get s = 23131131131. * Step 4: ℓ = 2 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 3. * Step 2, Cut once: we get s = 231 and c = 31131131. * Step 3, Paste s_ℓ = 1 time: we get s = 23131131131. * Step 4: ℓ = 3 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 4. * Step 2, Cut once: we get s = 2313 and c = 1131131. * Step 3, Paste s_ℓ = 3 times: we get s = 2313113113111311311131131. * Step 4: ℓ = 4 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 5. * Step 2, Cut once: we get s = 23131 and c = 13113111311311131131. * Step 3, Paste s_ℓ = 1 times: we get s = 2313113113111311311131131. * Step 4: ℓ = 5 = x, so we stop. At the end of the procedure, s has length 25. Tags: implementation, math Correct Solution: ``` M = int(1e9+7) n = int(input()) while n>0: n -= 1 x = int(input()) s = input() idx = 0 length = len(s) while length < x: t = ord(s[idx])-ord('1') s += s[idx+1:]*t length += (length-idx-1)*t idx += 1 while idx != x: t = ord(s[idx])-ord('1') length += ((length-idx-1)*t)%M idx += 1 print(length%M) ```
104,540
Provide tags and a correct Python 3 solution for this coding contest problem. We start with a string s consisting only of the digits 1, 2, or 3. The length of s is denoted by |s|. For each i from 1 to |s|, the i-th character of s is denoted by s_i. There is one cursor. The cursor's location ℓ is denoted by an integer in \{0, …, |s|\}, with the following meaning: * If ℓ = 0, then the cursor is located before the first character of s. * If ℓ = |s|, then the cursor is located right after the last character of s. * If 0 < ℓ < |s|, then the cursor is located between s_ℓ and s_{ℓ+1}. We denote by s_left the string to the left of the cursor and s_right the string to the right of the cursor. We also have a string c, which we call our clipboard, which starts out as empty. There are three types of actions: * The Move action. Move the cursor one step to the right. This increments ℓ once. * The Cut action. Set c ← s_right, then set s ← s_left. * The Paste action. Append the value of c to the end of the string s. Note that this doesn't modify c. The cursor initially starts at ℓ = 0. Then, we perform the following procedure: 1. Perform the Move action once. 2. Perform the Cut action once. 3. Perform the Paste action s_ℓ times. 4. If ℓ = x, stop. Otherwise, return to step 1. You're given the initial string s and the integer x. What is the length of s when the procedure stops? Since this value may be very large, only find it modulo 10^9 + 7. It is guaranteed that ℓ ≤ |s| at any time. Input The first line of input contains a single integer t (1 ≤ t ≤ 1000) denoting the number of test cases. The next lines contain descriptions of the test cases. The first line of each test case contains a single integer x (1 ≤ x ≤ 10^6). The second line of each test case consists of the initial string s (1 ≤ |s| ≤ 500). It is guaranteed, that s consists of the characters "1", "2", "3". It is guaranteed that the sum of x in a single file is at most 10^6. It is guaranteed that in each test case before the procedure will stop it will be true that ℓ ≤ |s| at any time. Output For each test case, output a single line containing a single integer denoting the answer for that test case modulo 10^9 + 7. Example Input 4 5 231 7 2323 6 333 24 133321333 Output 25 1438 1101 686531475 Note Let's illustrate what happens with the first test case. Initially, we have s = 231. Initially, ℓ = 0 and c = \varepsilon (the empty string). The following things happen if we follow the procedure above: * Step 1, Move once: we get ℓ = 1. * Step 2, Cut once: we get s = 2 and c = 31. * Step 3, Paste s_ℓ = 2 times: we get s = 23131. * Step 4: ℓ = 1 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 2. * Step 2, Cut once: we get s = 23 and c = 131. * Step 3, Paste s_ℓ = 3 times: we get s = 23131131131. * Step 4: ℓ = 2 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 3. * Step 2, Cut once: we get s = 231 and c = 31131131. * Step 3, Paste s_ℓ = 1 time: we get s = 23131131131. * Step 4: ℓ = 3 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 4. * Step 2, Cut once: we get s = 2313 and c = 1131131. * Step 3, Paste s_ℓ = 3 times: we get s = 2313113113111311311131131. * Step 4: ℓ = 4 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 5. * Step 2, Cut once: we get s = 23131 and c = 13113111311311131131. * Step 3, Paste s_ℓ = 1 times: we get s = 2313113113111311311131131. * Step 4: ℓ = 5 = x, so we stop. At the end of the procedure, s has length 25. Tags: implementation, math Correct Solution: ``` for _ in range(int(input())): x = int(input()) s = list(input()) l = 0 ans = len(s) while(l<x): if(ans>=x): break temp = len(s) ans+=(int(s[l])-1)*(temp-l-1) for i in range(int(s[l])-1): if(len(s)>x): break for j in range(l+1,temp): s.append(s[j]) if(len(s)>x): break l+=1 while(l<x): temp = ans ans+=(int(s[l])-1)*(temp-l-1) ans = ans%(10**9+7) l+=1 print(ans) ```
104,541
Provide tags and a correct Python 3 solution for this coding contest problem. We start with a string s consisting only of the digits 1, 2, or 3. The length of s is denoted by |s|. For each i from 1 to |s|, the i-th character of s is denoted by s_i. There is one cursor. The cursor's location ℓ is denoted by an integer in \{0, …, |s|\}, with the following meaning: * If ℓ = 0, then the cursor is located before the first character of s. * If ℓ = |s|, then the cursor is located right after the last character of s. * If 0 < ℓ < |s|, then the cursor is located between s_ℓ and s_{ℓ+1}. We denote by s_left the string to the left of the cursor and s_right the string to the right of the cursor. We also have a string c, which we call our clipboard, which starts out as empty. There are three types of actions: * The Move action. Move the cursor one step to the right. This increments ℓ once. * The Cut action. Set c ← s_right, then set s ← s_left. * The Paste action. Append the value of c to the end of the string s. Note that this doesn't modify c. The cursor initially starts at ℓ = 0. Then, we perform the following procedure: 1. Perform the Move action once. 2. Perform the Cut action once. 3. Perform the Paste action s_ℓ times. 4. If ℓ = x, stop. Otherwise, return to step 1. You're given the initial string s and the integer x. What is the length of s when the procedure stops? Since this value may be very large, only find it modulo 10^9 + 7. It is guaranteed that ℓ ≤ |s| at any time. Input The first line of input contains a single integer t (1 ≤ t ≤ 1000) denoting the number of test cases. The next lines contain descriptions of the test cases. The first line of each test case contains a single integer x (1 ≤ x ≤ 10^6). The second line of each test case consists of the initial string s (1 ≤ |s| ≤ 500). It is guaranteed, that s consists of the characters "1", "2", "3". It is guaranteed that the sum of x in a single file is at most 10^6. It is guaranteed that in each test case before the procedure will stop it will be true that ℓ ≤ |s| at any time. Output For each test case, output a single line containing a single integer denoting the answer for that test case modulo 10^9 + 7. Example Input 4 5 231 7 2323 6 333 24 133321333 Output 25 1438 1101 686531475 Note Let's illustrate what happens with the first test case. Initially, we have s = 231. Initially, ℓ = 0 and c = \varepsilon (the empty string). The following things happen if we follow the procedure above: * Step 1, Move once: we get ℓ = 1. * Step 2, Cut once: we get s = 2 and c = 31. * Step 3, Paste s_ℓ = 2 times: we get s = 23131. * Step 4: ℓ = 1 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 2. * Step 2, Cut once: we get s = 23 and c = 131. * Step 3, Paste s_ℓ = 3 times: we get s = 23131131131. * Step 4: ℓ = 2 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 3. * Step 2, Cut once: we get s = 231 and c = 31131131. * Step 3, Paste s_ℓ = 1 time: we get s = 23131131131. * Step 4: ℓ = 3 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 4. * Step 2, Cut once: we get s = 2313 and c = 1131131. * Step 3, Paste s_ℓ = 3 times: we get s = 2313113113111311311131131. * Step 4: ℓ = 4 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 5. * Step 2, Cut once: we get s = 23131 and c = 13113111311311131131. * Step 3, Paste s_ℓ = 1 times: we get s = 2313113113111311311131131. * Step 4: ℓ = 5 = x, so we stop. At the end of the procedure, s has length 25. Tags: implementation, math Correct Solution: ``` M = 1000000007 t = int(input()) while t: t += -1 x = int(input()) s = input() i = 0 while len(s) < x: s += s[i + 1: ] * (int(s[i]) - 1) i += 1 n = len(s) for j in range(i, x): tmp = n - (j + 1) n = j + 1 + tmp * (int(s[j])) n = n % M print(n % M) ```
104,542
Provide tags and a correct Python 3 solution for this coding contest problem. We start with a string s consisting only of the digits 1, 2, or 3. The length of s is denoted by |s|. For each i from 1 to |s|, the i-th character of s is denoted by s_i. There is one cursor. The cursor's location ℓ is denoted by an integer in \{0, …, |s|\}, with the following meaning: * If ℓ = 0, then the cursor is located before the first character of s. * If ℓ = |s|, then the cursor is located right after the last character of s. * If 0 < ℓ < |s|, then the cursor is located between s_ℓ and s_{ℓ+1}. We denote by s_left the string to the left of the cursor and s_right the string to the right of the cursor. We also have a string c, which we call our clipboard, which starts out as empty. There are three types of actions: * The Move action. Move the cursor one step to the right. This increments ℓ once. * The Cut action. Set c ← s_right, then set s ← s_left. * The Paste action. Append the value of c to the end of the string s. Note that this doesn't modify c. The cursor initially starts at ℓ = 0. Then, we perform the following procedure: 1. Perform the Move action once. 2. Perform the Cut action once. 3. Perform the Paste action s_ℓ times. 4. If ℓ = x, stop. Otherwise, return to step 1. You're given the initial string s and the integer x. What is the length of s when the procedure stops? Since this value may be very large, only find it modulo 10^9 + 7. It is guaranteed that ℓ ≤ |s| at any time. Input The first line of input contains a single integer t (1 ≤ t ≤ 1000) denoting the number of test cases. The next lines contain descriptions of the test cases. The first line of each test case contains a single integer x (1 ≤ x ≤ 10^6). The second line of each test case consists of the initial string s (1 ≤ |s| ≤ 500). It is guaranteed, that s consists of the characters "1", "2", "3". It is guaranteed that the sum of x in a single file is at most 10^6. It is guaranteed that in each test case before the procedure will stop it will be true that ℓ ≤ |s| at any time. Output For each test case, output a single line containing a single integer denoting the answer for that test case modulo 10^9 + 7. Example Input 4 5 231 7 2323 6 333 24 133321333 Output 25 1438 1101 686531475 Note Let's illustrate what happens with the first test case. Initially, we have s = 231. Initially, ℓ = 0 and c = \varepsilon (the empty string). The following things happen if we follow the procedure above: * Step 1, Move once: we get ℓ = 1. * Step 2, Cut once: we get s = 2 and c = 31. * Step 3, Paste s_ℓ = 2 times: we get s = 23131. * Step 4: ℓ = 1 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 2. * Step 2, Cut once: we get s = 23 and c = 131. * Step 3, Paste s_ℓ = 3 times: we get s = 23131131131. * Step 4: ℓ = 2 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 3. * Step 2, Cut once: we get s = 231 and c = 31131131. * Step 3, Paste s_ℓ = 1 time: we get s = 23131131131. * Step 4: ℓ = 3 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 4. * Step 2, Cut once: we get s = 2313 and c = 1131131. * Step 3, Paste s_ℓ = 3 times: we get s = 2313113113111311311131131. * Step 4: ℓ = 4 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 5. * Step 2, Cut once: we get s = 23131 and c = 13113111311311131131. * Step 3, Paste s_ℓ = 1 times: we get s = 2313113113111311311131131. * Step 4: ℓ = 5 = x, so we stop. At the end of the procedure, s has length 25. Tags: implementation, math Correct Solution: ``` def main(): TT = int(input()) for _ in range(TT): x = int(input()) s = [int(c) for c in input().strip()] ans = len(s) for l in range(0, x): ans += (ans - l - 1) * (s[l] - 1) ans %= 1000000007 end = len(s) for _ in range(1, s[l]): if len(s) > x + 1: break for c in range(l + 1, end): if len(s) > x + 1: break s.append(s[c]) print(ans) if __name__ == '__main__': main() ```
104,543
Provide tags and a correct Python 3 solution for this coding contest problem. We start with a string s consisting only of the digits 1, 2, or 3. The length of s is denoted by |s|. For each i from 1 to |s|, the i-th character of s is denoted by s_i. There is one cursor. The cursor's location ℓ is denoted by an integer in \{0, …, |s|\}, with the following meaning: * If ℓ = 0, then the cursor is located before the first character of s. * If ℓ = |s|, then the cursor is located right after the last character of s. * If 0 < ℓ < |s|, then the cursor is located between s_ℓ and s_{ℓ+1}. We denote by s_left the string to the left of the cursor and s_right the string to the right of the cursor. We also have a string c, which we call our clipboard, which starts out as empty. There are three types of actions: * The Move action. Move the cursor one step to the right. This increments ℓ once. * The Cut action. Set c ← s_right, then set s ← s_left. * The Paste action. Append the value of c to the end of the string s. Note that this doesn't modify c. The cursor initially starts at ℓ = 0. Then, we perform the following procedure: 1. Perform the Move action once. 2. Perform the Cut action once. 3. Perform the Paste action s_ℓ times. 4. If ℓ = x, stop. Otherwise, return to step 1. You're given the initial string s and the integer x. What is the length of s when the procedure stops? Since this value may be very large, only find it modulo 10^9 + 7. It is guaranteed that ℓ ≤ |s| at any time. Input The first line of input contains a single integer t (1 ≤ t ≤ 1000) denoting the number of test cases. The next lines contain descriptions of the test cases. The first line of each test case contains a single integer x (1 ≤ x ≤ 10^6). The second line of each test case consists of the initial string s (1 ≤ |s| ≤ 500). It is guaranteed, that s consists of the characters "1", "2", "3". It is guaranteed that the sum of x in a single file is at most 10^6. It is guaranteed that in each test case before the procedure will stop it will be true that ℓ ≤ |s| at any time. Output For each test case, output a single line containing a single integer denoting the answer for that test case modulo 10^9 + 7. Example Input 4 5 231 7 2323 6 333 24 133321333 Output 25 1438 1101 686531475 Note Let's illustrate what happens with the first test case. Initially, we have s = 231. Initially, ℓ = 0 and c = \varepsilon (the empty string). The following things happen if we follow the procedure above: * Step 1, Move once: we get ℓ = 1. * Step 2, Cut once: we get s = 2 and c = 31. * Step 3, Paste s_ℓ = 2 times: we get s = 23131. * Step 4: ℓ = 1 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 2. * Step 2, Cut once: we get s = 23 and c = 131. * Step 3, Paste s_ℓ = 3 times: we get s = 23131131131. * Step 4: ℓ = 2 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 3. * Step 2, Cut once: we get s = 231 and c = 31131131. * Step 3, Paste s_ℓ = 1 time: we get s = 23131131131. * Step 4: ℓ = 3 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 4. * Step 2, Cut once: we get s = 2313 and c = 1131131. * Step 3, Paste s_ℓ = 3 times: we get s = 2313113113111311311131131. * Step 4: ℓ = 4 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 5. * Step 2, Cut once: we get s = 23131 and c = 13113111311311131131. * Step 3, Paste s_ℓ = 1 times: we get s = 2313113113111311311131131. * Step 4: ℓ = 5 = x, so we stop. At the end of the procedure, s has length 25. Tags: implementation, math Correct Solution: ``` ttt = int(input()) mod = 10**9 + 7 s = "#"*(10**6 + 1500) s=list(s) for bo in range(ttt): x=int(input()) st=input() s[1:len(st)+1]=list(st) siz=len(st) p = 0 while siz < x: p += 1 whe = siz for de4d in range(int(s[p])-1): for k in range(p+1,whe+1): siz += 1 s[siz] = s[k] if (siz>x): break if (siz>x): break if (siz>x): break ans = len(st) for i in range(1,x+1): ans = i + (ans-i)*int(s[i]) ans = ans%mod print(ans) ```
104,544
Provide tags and a correct Python 3 solution for this coding contest problem. We start with a string s consisting only of the digits 1, 2, or 3. The length of s is denoted by |s|. For each i from 1 to |s|, the i-th character of s is denoted by s_i. There is one cursor. The cursor's location ℓ is denoted by an integer in \{0, …, |s|\}, with the following meaning: * If ℓ = 0, then the cursor is located before the first character of s. * If ℓ = |s|, then the cursor is located right after the last character of s. * If 0 < ℓ < |s|, then the cursor is located between s_ℓ and s_{ℓ+1}. We denote by s_left the string to the left of the cursor and s_right the string to the right of the cursor. We also have a string c, which we call our clipboard, which starts out as empty. There are three types of actions: * The Move action. Move the cursor one step to the right. This increments ℓ once. * The Cut action. Set c ← s_right, then set s ← s_left. * The Paste action. Append the value of c to the end of the string s. Note that this doesn't modify c. The cursor initially starts at ℓ = 0. Then, we perform the following procedure: 1. Perform the Move action once. 2. Perform the Cut action once. 3. Perform the Paste action s_ℓ times. 4. If ℓ = x, stop. Otherwise, return to step 1. You're given the initial string s and the integer x. What is the length of s when the procedure stops? Since this value may be very large, only find it modulo 10^9 + 7. It is guaranteed that ℓ ≤ |s| at any time. Input The first line of input contains a single integer t (1 ≤ t ≤ 1000) denoting the number of test cases. The next lines contain descriptions of the test cases. The first line of each test case contains a single integer x (1 ≤ x ≤ 10^6). The second line of each test case consists of the initial string s (1 ≤ |s| ≤ 500). It is guaranteed, that s consists of the characters "1", "2", "3". It is guaranteed that the sum of x in a single file is at most 10^6. It is guaranteed that in each test case before the procedure will stop it will be true that ℓ ≤ |s| at any time. Output For each test case, output a single line containing a single integer denoting the answer for that test case modulo 10^9 + 7. Example Input 4 5 231 7 2323 6 333 24 133321333 Output 25 1438 1101 686531475 Note Let's illustrate what happens with the first test case. Initially, we have s = 231. Initially, ℓ = 0 and c = \varepsilon (the empty string). The following things happen if we follow the procedure above: * Step 1, Move once: we get ℓ = 1. * Step 2, Cut once: we get s = 2 and c = 31. * Step 3, Paste s_ℓ = 2 times: we get s = 23131. * Step 4: ℓ = 1 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 2. * Step 2, Cut once: we get s = 23 and c = 131. * Step 3, Paste s_ℓ = 3 times: we get s = 23131131131. * Step 4: ℓ = 2 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 3. * Step 2, Cut once: we get s = 231 and c = 31131131. * Step 3, Paste s_ℓ = 1 time: we get s = 23131131131. * Step 4: ℓ = 3 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 4. * Step 2, Cut once: we get s = 2313 and c = 1131131. * Step 3, Paste s_ℓ = 3 times: we get s = 2313113113111311311131131. * Step 4: ℓ = 4 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 5. * Step 2, Cut once: we get s = 23131 and c = 13113111311311131131. * Step 3, Paste s_ℓ = 1 times: we get s = 2313113113111311311131131. * Step 4: ℓ = 5 = x, so we stop. At the end of the procedure, s has length 25. Tags: implementation, math Correct Solution: ``` t = int(input()) ans = [] arr = [None] * (10 ** 6) cur = 0 MOD = 10 ** 9 + 7 for _ in range(t): x, s = int(input()), list(map(int, str(input()))) max_p = cur + x for i in range(cur, min(max_p, cur + len(s))): arr[i] = s[i - cur] def copy(start, length, times): b = start + length for i in range(times): for j in range(length): if b >= max_p: return arr[b] = arr[start + j] b += 1 val = len(s) cnt = 1 while x: if arr[max_p - 1] is None and arr[cur] > 1: copy(cur + 1, val - cnt, arr[cur] - 1) val = (cnt + (val - cnt) * arr[cur]) % MOD cnt += 1 cur += 1 x -= 1 ans.append(val) for a in ans: print(a) ```
104,545
Provide tags and a correct Python 3 solution for this coding contest problem. We start with a string s consisting only of the digits 1, 2, or 3. The length of s is denoted by |s|. For each i from 1 to |s|, the i-th character of s is denoted by s_i. There is one cursor. The cursor's location ℓ is denoted by an integer in \{0, …, |s|\}, with the following meaning: * If ℓ = 0, then the cursor is located before the first character of s. * If ℓ = |s|, then the cursor is located right after the last character of s. * If 0 < ℓ < |s|, then the cursor is located between s_ℓ and s_{ℓ+1}. We denote by s_left the string to the left of the cursor and s_right the string to the right of the cursor. We also have a string c, which we call our clipboard, which starts out as empty. There are three types of actions: * The Move action. Move the cursor one step to the right. This increments ℓ once. * The Cut action. Set c ← s_right, then set s ← s_left. * The Paste action. Append the value of c to the end of the string s. Note that this doesn't modify c. The cursor initially starts at ℓ = 0. Then, we perform the following procedure: 1. Perform the Move action once. 2. Perform the Cut action once. 3. Perform the Paste action s_ℓ times. 4. If ℓ = x, stop. Otherwise, return to step 1. You're given the initial string s and the integer x. What is the length of s when the procedure stops? Since this value may be very large, only find it modulo 10^9 + 7. It is guaranteed that ℓ ≤ |s| at any time. Input The first line of input contains a single integer t (1 ≤ t ≤ 1000) denoting the number of test cases. The next lines contain descriptions of the test cases. The first line of each test case contains a single integer x (1 ≤ x ≤ 10^6). The second line of each test case consists of the initial string s (1 ≤ |s| ≤ 500). It is guaranteed, that s consists of the characters "1", "2", "3". It is guaranteed that the sum of x in a single file is at most 10^6. It is guaranteed that in each test case before the procedure will stop it will be true that ℓ ≤ |s| at any time. Output For each test case, output a single line containing a single integer denoting the answer for that test case modulo 10^9 + 7. Example Input 4 5 231 7 2323 6 333 24 133321333 Output 25 1438 1101 686531475 Note Let's illustrate what happens with the first test case. Initially, we have s = 231. Initially, ℓ = 0 and c = \varepsilon (the empty string). The following things happen if we follow the procedure above: * Step 1, Move once: we get ℓ = 1. * Step 2, Cut once: we get s = 2 and c = 31. * Step 3, Paste s_ℓ = 2 times: we get s = 23131. * Step 4: ℓ = 1 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 2. * Step 2, Cut once: we get s = 23 and c = 131. * Step 3, Paste s_ℓ = 3 times: we get s = 23131131131. * Step 4: ℓ = 2 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 3. * Step 2, Cut once: we get s = 231 and c = 31131131. * Step 3, Paste s_ℓ = 1 time: we get s = 23131131131. * Step 4: ℓ = 3 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 4. * Step 2, Cut once: we get s = 2313 and c = 1131131. * Step 3, Paste s_ℓ = 3 times: we get s = 2313113113111311311131131. * Step 4: ℓ = 4 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 5. * Step 2, Cut once: we get s = 23131 and c = 13113111311311131131. * Step 3, Paste s_ℓ = 1 times: we get s = 2313113113111311311131131. * Step 4: ℓ = 5 = x, so we stop. At the end of the procedure, s has length 25. Tags: implementation, math Correct Solution: ``` def solve(s,x): n = len(s) mod = 10**9 + 7 for i in range(x): n += (n-i-1)*(int(s[i])-1) n %= mod if len(s) < x: s += s[i+1:]*(int(s[i])-1) return n for _ in range(int(input())): x = int(input()) s = input() print(solve(s,x)) ```
104,546
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. We start with a string s consisting only of the digits 1, 2, or 3. The length of s is denoted by |s|. For each i from 1 to |s|, the i-th character of s is denoted by s_i. There is one cursor. The cursor's location ℓ is denoted by an integer in \{0, …, |s|\}, with the following meaning: * If ℓ = 0, then the cursor is located before the first character of s. * If ℓ = |s|, then the cursor is located right after the last character of s. * If 0 < ℓ < |s|, then the cursor is located between s_ℓ and s_{ℓ+1}. We denote by s_left the string to the left of the cursor and s_right the string to the right of the cursor. We also have a string c, which we call our clipboard, which starts out as empty. There are three types of actions: * The Move action. Move the cursor one step to the right. This increments ℓ once. * The Cut action. Set c ← s_right, then set s ← s_left. * The Paste action. Append the value of c to the end of the string s. Note that this doesn't modify c. The cursor initially starts at ℓ = 0. Then, we perform the following procedure: 1. Perform the Move action once. 2. Perform the Cut action once. 3. Perform the Paste action s_ℓ times. 4. If ℓ = x, stop. Otherwise, return to step 1. You're given the initial string s and the integer x. What is the length of s when the procedure stops? Since this value may be very large, only find it modulo 10^9 + 7. It is guaranteed that ℓ ≤ |s| at any time. Input The first line of input contains a single integer t (1 ≤ t ≤ 1000) denoting the number of test cases. The next lines contain descriptions of the test cases. The first line of each test case contains a single integer x (1 ≤ x ≤ 10^6). The second line of each test case consists of the initial string s (1 ≤ |s| ≤ 500). It is guaranteed, that s consists of the characters "1", "2", "3". It is guaranteed that the sum of x in a single file is at most 10^6. It is guaranteed that in each test case before the procedure will stop it will be true that ℓ ≤ |s| at any time. Output For each test case, output a single line containing a single integer denoting the answer for that test case modulo 10^9 + 7. Example Input 4 5 231 7 2323 6 333 24 133321333 Output 25 1438 1101 686531475 Note Let's illustrate what happens with the first test case. Initially, we have s = 231. Initially, ℓ = 0 and c = \varepsilon (the empty string). The following things happen if we follow the procedure above: * Step 1, Move once: we get ℓ = 1. * Step 2, Cut once: we get s = 2 and c = 31. * Step 3, Paste s_ℓ = 2 times: we get s = 23131. * Step 4: ℓ = 1 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 2. * Step 2, Cut once: we get s = 23 and c = 131. * Step 3, Paste s_ℓ = 3 times: we get s = 23131131131. * Step 4: ℓ = 2 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 3. * Step 2, Cut once: we get s = 231 and c = 31131131. * Step 3, Paste s_ℓ = 1 time: we get s = 23131131131. * Step 4: ℓ = 3 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 4. * Step 2, Cut once: we get s = 2313 and c = 1131131. * Step 3, Paste s_ℓ = 3 times: we get s = 2313113113111311311131131. * Step 4: ℓ = 4 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 5. * Step 2, Cut once: we get s = 23131 and c = 13113111311311131131. * Step 3, Paste s_ℓ = 1 times: we get s = 2313113113111311311131131. * Step 4: ℓ = 5 = x, so we stop. At the end of the procedure, s has length 25. Submitted Solution: ``` for _ in range(int(input())): x=int(input()) a=input() l=len(a) a=[i for i in a] ans=l p=0 m=10**9+7 while ans<x: for j in range(int(a[p])-1): for i in range(p+1,ans): a.append(a[i]) ans+=(int(a[p])-1)*((ans-p-1+m)%m) p+=1 for j in range(p,x): ans+=(int(a[j])-1)*((ans-j-1+m)%m) ans%=m print(ans) ``` Yes
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. We start with a string s consisting only of the digits 1, 2, or 3. The length of s is denoted by |s|. For each i from 1 to |s|, the i-th character of s is denoted by s_i. There is one cursor. The cursor's location ℓ is denoted by an integer in \{0, …, |s|\}, with the following meaning: * If ℓ = 0, then the cursor is located before the first character of s. * If ℓ = |s|, then the cursor is located right after the last character of s. * If 0 < ℓ < |s|, then the cursor is located between s_ℓ and s_{ℓ+1}. We denote by s_left the string to the left of the cursor and s_right the string to the right of the cursor. We also have a string c, which we call our clipboard, which starts out as empty. There are three types of actions: * The Move action. Move the cursor one step to the right. This increments ℓ once. * The Cut action. Set c ← s_right, then set s ← s_left. * The Paste action. Append the value of c to the end of the string s. Note that this doesn't modify c. The cursor initially starts at ℓ = 0. Then, we perform the following procedure: 1. Perform the Move action once. 2. Perform the Cut action once. 3. Perform the Paste action s_ℓ times. 4. If ℓ = x, stop. Otherwise, return to step 1. You're given the initial string s and the integer x. What is the length of s when the procedure stops? Since this value may be very large, only find it modulo 10^9 + 7. It is guaranteed that ℓ ≤ |s| at any time. Input The first line of input contains a single integer t (1 ≤ t ≤ 1000) denoting the number of test cases. The next lines contain descriptions of the test cases. The first line of each test case contains a single integer x (1 ≤ x ≤ 10^6). The second line of each test case consists of the initial string s (1 ≤ |s| ≤ 500). It is guaranteed, that s consists of the characters "1", "2", "3". It is guaranteed that the sum of x in a single file is at most 10^6. It is guaranteed that in each test case before the procedure will stop it will be true that ℓ ≤ |s| at any time. Output For each test case, output a single line containing a single integer denoting the answer for that test case modulo 10^9 + 7. Example Input 4 5 231 7 2323 6 333 24 133321333 Output 25 1438 1101 686531475 Note Let's illustrate what happens with the first test case. Initially, we have s = 231. Initially, ℓ = 0 and c = \varepsilon (the empty string). The following things happen if we follow the procedure above: * Step 1, Move once: we get ℓ = 1. * Step 2, Cut once: we get s = 2 and c = 31. * Step 3, Paste s_ℓ = 2 times: we get s = 23131. * Step 4: ℓ = 1 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 2. * Step 2, Cut once: we get s = 23 and c = 131. * Step 3, Paste s_ℓ = 3 times: we get s = 23131131131. * Step 4: ℓ = 2 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 3. * Step 2, Cut once: we get s = 231 and c = 31131131. * Step 3, Paste s_ℓ = 1 time: we get s = 23131131131. * Step 4: ℓ = 3 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 4. * Step 2, Cut once: we get s = 2313 and c = 1131131. * Step 3, Paste s_ℓ = 3 times: we get s = 2313113113111311311131131. * Step 4: ℓ = 4 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 5. * Step 2, Cut once: we get s = 23131 and c = 13113111311311131131. * Step 3, Paste s_ℓ = 1 times: we get s = 2313113113111311311131131. * Step 4: ℓ = 5 = x, so we stop. At the end of the procedure, s has length 25. Submitted Solution: ``` #TLE # import sys, os.path # import math # from collections import defaultdict,deque # input = sys.stdin.readline # I = lambda : list(map(int,input().split())) # S = lambda : list(map(str,input())) # def main(): # # s1 = [0]*((2*(10**6))+1) # t,=I() # for t1 in range(t): # x, = I() # s1 = str(input()).rstrip('\n') # # for i in range(len(s2)): # # s1[i] = int(s2[i]) # l = 0 # count = 0 # count1 = len(s1) # count1%=((10**9)+7) # for i in range(x): # k = int(s1[i]) # count1-=1 # count1%=((10**9)+7) # if count1>x: # count1*=k # count1%=((10**9)+7) # else: # l1 = len(s1) # for j in range(k-1): # for l in range(i+1,l1): # s1+=s1[l] # count1*=k # count1%=((10**9)+7) # count1+=x # count1%=((10**9)+7) # print(count1) # main() # import sys, os.path import math from collections import defaultdict,deque input = sys.stdin.readline I = lambda : list(map(int,input().split())) S = lambda : list(map(str,input())) def main(): # s1 = [0]*((2*(10**6))+1) t,=I() for t1 in range(t): x, = I() s2 = str(input()).rstrip('\n') s1 = [] for i in range(len(s2)): if i>x: break s1.append(int(s2[i])) count1 = len(s2) count1%=((10**9)+7) for i in range(x): k = int(s1[i]) count1-=1 count1%=((10**9)+7) if len(s1)>x: count1*=k count1%=((10**9)+7) else: if k==1: continue X = s1[i+1:] l1 = len(s1) for j in range(k-1): if len(s1)<x: s1.extend(X) count1*=k count1%=((10**9)+7) count1+=x count1%=((10**9)+7) print(count1) main() # import sys # input = sys.stdin.readline # mod = 10 ** 9 + 7 # t = int(input()) # for _ in range(t): # x = int(input()) # s = input().rstrip('\n') # X = [] # for i, si in enumerate(s): # if i == x: # break # X.append(int(s[i])) # ans = len(s) # for i in range(x): # ans = (ans + (ans - i - 1) * (X[i] - 1)) % mod # if len(X) < x: # if X[i] == 1: # continue # X_ = X[i + 1:] # for j in range(X[i] - 1): # if len(X) < x: # X.extend(X_) # print(ans) ``` Yes
104,548
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. We start with a string s consisting only of the digits 1, 2, or 3. The length of s is denoted by |s|. For each i from 1 to |s|, the i-th character of s is denoted by s_i. There is one cursor. The cursor's location ℓ is denoted by an integer in \{0, …, |s|\}, with the following meaning: * If ℓ = 0, then the cursor is located before the first character of s. * If ℓ = |s|, then the cursor is located right after the last character of s. * If 0 < ℓ < |s|, then the cursor is located between s_ℓ and s_{ℓ+1}. We denote by s_left the string to the left of the cursor and s_right the string to the right of the cursor. We also have a string c, which we call our clipboard, which starts out as empty. There are three types of actions: * The Move action. Move the cursor one step to the right. This increments ℓ once. * The Cut action. Set c ← s_right, then set s ← s_left. * The Paste action. Append the value of c to the end of the string s. Note that this doesn't modify c. The cursor initially starts at ℓ = 0. Then, we perform the following procedure: 1. Perform the Move action once. 2. Perform the Cut action once. 3. Perform the Paste action s_ℓ times. 4. If ℓ = x, stop. Otherwise, return to step 1. You're given the initial string s and the integer x. What is the length of s when the procedure stops? Since this value may be very large, only find it modulo 10^9 + 7. It is guaranteed that ℓ ≤ |s| at any time. Input The first line of input contains a single integer t (1 ≤ t ≤ 1000) denoting the number of test cases. The next lines contain descriptions of the test cases. The first line of each test case contains a single integer x (1 ≤ x ≤ 10^6). The second line of each test case consists of the initial string s (1 ≤ |s| ≤ 500). It is guaranteed, that s consists of the characters "1", "2", "3". It is guaranteed that the sum of x in a single file is at most 10^6. It is guaranteed that in each test case before the procedure will stop it will be true that ℓ ≤ |s| at any time. Output For each test case, output a single line containing a single integer denoting the answer for that test case modulo 10^9 + 7. Example Input 4 5 231 7 2323 6 333 24 133321333 Output 25 1438 1101 686531475 Note Let's illustrate what happens with the first test case. Initially, we have s = 231. Initially, ℓ = 0 and c = \varepsilon (the empty string). The following things happen if we follow the procedure above: * Step 1, Move once: we get ℓ = 1. * Step 2, Cut once: we get s = 2 and c = 31. * Step 3, Paste s_ℓ = 2 times: we get s = 23131. * Step 4: ℓ = 1 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 2. * Step 2, Cut once: we get s = 23 and c = 131. * Step 3, Paste s_ℓ = 3 times: we get s = 23131131131. * Step 4: ℓ = 2 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 3. * Step 2, Cut once: we get s = 231 and c = 31131131. * Step 3, Paste s_ℓ = 1 time: we get s = 23131131131. * Step 4: ℓ = 3 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 4. * Step 2, Cut once: we get s = 2313 and c = 1131131. * Step 3, Paste s_ℓ = 3 times: we get s = 2313113113111311311131131. * Step 4: ℓ = 4 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 5. * Step 2, Cut once: we get s = 23131 and c = 13113111311311131131. * Step 3, Paste s_ℓ = 1 times: we get s = 2313113113111311311131131. * Step 4: ℓ = 5 = x, so we stop. At the end of the procedure, s has length 25. Submitted Solution: ``` import time import sys MOD = 1e9 + 7 # f = open('test.txt', 'w+') # f.write("1\n333047\n") # f.write('1'*300 + '2' + '1'*20 + '2') # f.seek(0) f = sys.stdin t1 = time.time() for t in range(int(f.readline())): x, s = int(f.readline().rstrip()), f.readline().rstrip() i = 0 while len(s) < x: i += 1 s += s[i:] * (int(s[i - 1])-1) answer = len(s) while i < x: i += 1 answer = (answer + (answer - i) * (int(s[i - 1]) - 1)) % MOD print(int(answer)) # print("--- %s seconds ---" % (time.time() - t1)) ``` Yes
104,549
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. We start with a string s consisting only of the digits 1, 2, or 3. The length of s is denoted by |s|. For each i from 1 to |s|, the i-th character of s is denoted by s_i. There is one cursor. The cursor's location ℓ is denoted by an integer in \{0, …, |s|\}, with the following meaning: * If ℓ = 0, then the cursor is located before the first character of s. * If ℓ = |s|, then the cursor is located right after the last character of s. * If 0 < ℓ < |s|, then the cursor is located between s_ℓ and s_{ℓ+1}. We denote by s_left the string to the left of the cursor and s_right the string to the right of the cursor. We also have a string c, which we call our clipboard, which starts out as empty. There are three types of actions: * The Move action. Move the cursor one step to the right. This increments ℓ once. * The Cut action. Set c ← s_right, then set s ← s_left. * The Paste action. Append the value of c to the end of the string s. Note that this doesn't modify c. The cursor initially starts at ℓ = 0. Then, we perform the following procedure: 1. Perform the Move action once. 2. Perform the Cut action once. 3. Perform the Paste action s_ℓ times. 4. If ℓ = x, stop. Otherwise, return to step 1. You're given the initial string s and the integer x. What is the length of s when the procedure stops? Since this value may be very large, only find it modulo 10^9 + 7. It is guaranteed that ℓ ≤ |s| at any time. Input The first line of input contains a single integer t (1 ≤ t ≤ 1000) denoting the number of test cases. The next lines contain descriptions of the test cases. The first line of each test case contains a single integer x (1 ≤ x ≤ 10^6). The second line of each test case consists of the initial string s (1 ≤ |s| ≤ 500). It is guaranteed, that s consists of the characters "1", "2", "3". It is guaranteed that the sum of x in a single file is at most 10^6. It is guaranteed that in each test case before the procedure will stop it will be true that ℓ ≤ |s| at any time. Output For each test case, output a single line containing a single integer denoting the answer for that test case modulo 10^9 + 7. Example Input 4 5 231 7 2323 6 333 24 133321333 Output 25 1438 1101 686531475 Note Let's illustrate what happens with the first test case. Initially, we have s = 231. Initially, ℓ = 0 and c = \varepsilon (the empty string). The following things happen if we follow the procedure above: * Step 1, Move once: we get ℓ = 1. * Step 2, Cut once: we get s = 2 and c = 31. * Step 3, Paste s_ℓ = 2 times: we get s = 23131. * Step 4: ℓ = 1 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 2. * Step 2, Cut once: we get s = 23 and c = 131. * Step 3, Paste s_ℓ = 3 times: we get s = 23131131131. * Step 4: ℓ = 2 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 3. * Step 2, Cut once: we get s = 231 and c = 31131131. * Step 3, Paste s_ℓ = 1 time: we get s = 23131131131. * Step 4: ℓ = 3 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 4. * Step 2, Cut once: we get s = 2313 and c = 1131131. * Step 3, Paste s_ℓ = 3 times: we get s = 2313113113111311311131131. * Step 4: ℓ = 4 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 5. * Step 2, Cut once: we get s = 23131 and c = 13113111311311131131. * Step 3, Paste s_ℓ = 1 times: we get s = 2313113113111311311131131. * Step 4: ℓ = 5 = x, so we stop. At the end of the procedure, s has length 25. Submitted Solution: ``` import sys T = int(sys.stdin.readline().strip()) for _ in range(T): x = int(sys.stdin.readline().strip()) s = list(sys.stdin.readline().strip()) ls = len(s) for l in range(x): t = ord(s[l]) - ord('0') - 1 ls = (ls + (ls - l - 1)*t) % ((10**9)+7) e = len(s) while len(s) <= x and t > 0: s += s[l+1:e] t -= 1 print(ls) ``` Yes
104,550
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. We start with a string s consisting only of the digits 1, 2, or 3. The length of s is denoted by |s|. For each i from 1 to |s|, the i-th character of s is denoted by s_i. There is one cursor. The cursor's location ℓ is denoted by an integer in \{0, …, |s|\}, with the following meaning: * If ℓ = 0, then the cursor is located before the first character of s. * If ℓ = |s|, then the cursor is located right after the last character of s. * If 0 < ℓ < |s|, then the cursor is located between s_ℓ and s_{ℓ+1}. We denote by s_left the string to the left of the cursor and s_right the string to the right of the cursor. We also have a string c, which we call our clipboard, which starts out as empty. There are three types of actions: * The Move action. Move the cursor one step to the right. This increments ℓ once. * The Cut action. Set c ← s_right, then set s ← s_left. * The Paste action. Append the value of c to the end of the string s. Note that this doesn't modify c. The cursor initially starts at ℓ = 0. Then, we perform the following procedure: 1. Perform the Move action once. 2. Perform the Cut action once. 3. Perform the Paste action s_ℓ times. 4. If ℓ = x, stop. Otherwise, return to step 1. You're given the initial string s and the integer x. What is the length of s when the procedure stops? Since this value may be very large, only find it modulo 10^9 + 7. It is guaranteed that ℓ ≤ |s| at any time. Input The first line of input contains a single integer t (1 ≤ t ≤ 1000) denoting the number of test cases. The next lines contain descriptions of the test cases. The first line of each test case contains a single integer x (1 ≤ x ≤ 10^6). The second line of each test case consists of the initial string s (1 ≤ |s| ≤ 500). It is guaranteed, that s consists of the characters "1", "2", "3". It is guaranteed that the sum of x in a single file is at most 10^6. It is guaranteed that in each test case before the procedure will stop it will be true that ℓ ≤ |s| at any time. Output For each test case, output a single line containing a single integer denoting the answer for that test case modulo 10^9 + 7. Example Input 4 5 231 7 2323 6 333 24 133321333 Output 25 1438 1101 686531475 Note Let's illustrate what happens with the first test case. Initially, we have s = 231. Initially, ℓ = 0 and c = \varepsilon (the empty string). The following things happen if we follow the procedure above: * Step 1, Move once: we get ℓ = 1. * Step 2, Cut once: we get s = 2 and c = 31. * Step 3, Paste s_ℓ = 2 times: we get s = 23131. * Step 4: ℓ = 1 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 2. * Step 2, Cut once: we get s = 23 and c = 131. * Step 3, Paste s_ℓ = 3 times: we get s = 23131131131. * Step 4: ℓ = 2 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 3. * Step 2, Cut once: we get s = 231 and c = 31131131. * Step 3, Paste s_ℓ = 1 time: we get s = 23131131131. * Step 4: ℓ = 3 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 4. * Step 2, Cut once: we get s = 2313 and c = 1131131. * Step 3, Paste s_ℓ = 3 times: we get s = 2313113113111311311131131. * Step 4: ℓ = 4 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 5. * Step 2, Cut once: we get s = 23131 and c = 13113111311311131131. * Step 3, Paste s_ℓ = 1 times: we get s = 2313113113111311311131131. * Step 4: ℓ = 5 = x, so we stop. At the end of the procedure, s has length 25. Submitted Solution: ``` t=int(input()) for i in range(t): x=int(input()) s=input() p=s l=0 while(l!=x): r=int(p[0]) p=p[1:] if r>1: p+=p if r>2: p+=p if (len(p)+l+1)>=x: l+=1 break l+=1 j=0 res=l y=len(p) while(l!=x): y-=1 y=y*int(p[j]) l+=1 res+=1 j+=1 print((res+y)%(10**9+7)) ``` No
104,551
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. We start with a string s consisting only of the digits 1, 2, or 3. The length of s is denoted by |s|. For each i from 1 to |s|, the i-th character of s is denoted by s_i. There is one cursor. The cursor's location ℓ is denoted by an integer in \{0, …, |s|\}, with the following meaning: * If ℓ = 0, then the cursor is located before the first character of s. * If ℓ = |s|, then the cursor is located right after the last character of s. * If 0 < ℓ < |s|, then the cursor is located between s_ℓ and s_{ℓ+1}. We denote by s_left the string to the left of the cursor and s_right the string to the right of the cursor. We also have a string c, which we call our clipboard, which starts out as empty. There are three types of actions: * The Move action. Move the cursor one step to the right. This increments ℓ once. * The Cut action. Set c ← s_right, then set s ← s_left. * The Paste action. Append the value of c to the end of the string s. Note that this doesn't modify c. The cursor initially starts at ℓ = 0. Then, we perform the following procedure: 1. Perform the Move action once. 2. Perform the Cut action once. 3. Perform the Paste action s_ℓ times. 4. If ℓ = x, stop. Otherwise, return to step 1. You're given the initial string s and the integer x. What is the length of s when the procedure stops? Since this value may be very large, only find it modulo 10^9 + 7. It is guaranteed that ℓ ≤ |s| at any time. Input The first line of input contains a single integer t (1 ≤ t ≤ 1000) denoting the number of test cases. The next lines contain descriptions of the test cases. The first line of each test case contains a single integer x (1 ≤ x ≤ 10^6). The second line of each test case consists of the initial string s (1 ≤ |s| ≤ 500). It is guaranteed, that s consists of the characters "1", "2", "3". It is guaranteed that the sum of x in a single file is at most 10^6. It is guaranteed that in each test case before the procedure will stop it will be true that ℓ ≤ |s| at any time. Output For each test case, output a single line containing a single integer denoting the answer for that test case modulo 10^9 + 7. Example Input 4 5 231 7 2323 6 333 24 133321333 Output 25 1438 1101 686531475 Note Let's illustrate what happens with the first test case. Initially, we have s = 231. Initially, ℓ = 0 and c = \varepsilon (the empty string). The following things happen if we follow the procedure above: * Step 1, Move once: we get ℓ = 1. * Step 2, Cut once: we get s = 2 and c = 31. * Step 3, Paste s_ℓ = 2 times: we get s = 23131. * Step 4: ℓ = 1 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 2. * Step 2, Cut once: we get s = 23 and c = 131. * Step 3, Paste s_ℓ = 3 times: we get s = 23131131131. * Step 4: ℓ = 2 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 3. * Step 2, Cut once: we get s = 231 and c = 31131131. * Step 3, Paste s_ℓ = 1 time: we get s = 23131131131. * Step 4: ℓ = 3 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 4. * Step 2, Cut once: we get s = 2313 and c = 1131131. * Step 3, Paste s_ℓ = 3 times: we get s = 2313113113111311311131131. * Step 4: ℓ = 4 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 5. * Step 2, Cut once: we get s = 23131 and c = 13113111311311131131. * Step 3, Paste s_ℓ = 1 times: we get s = 2313113113111311311131131. * Step 4: ℓ = 5 = x, so we stop. At the end of the procedure, s has length 25. Submitted Solution: ``` for _ in range(int(input())): x = int(input()) s = list(map(int, input())) ans = len(s) for i in range(1, x+1): ans = (i + (ans-i) * s[i-1])%1000000007 for _ in range(s[i-1]-1): if len(s) < x: s += s[i:] else: break print(ans) ``` No
104,552
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. We start with a string s consisting only of the digits 1, 2, or 3. The length of s is denoted by |s|. For each i from 1 to |s|, the i-th character of s is denoted by s_i. There is one cursor. The cursor's location ℓ is denoted by an integer in \{0, …, |s|\}, with the following meaning: * If ℓ = 0, then the cursor is located before the first character of s. * If ℓ = |s|, then the cursor is located right after the last character of s. * If 0 < ℓ < |s|, then the cursor is located between s_ℓ and s_{ℓ+1}. We denote by s_left the string to the left of the cursor and s_right the string to the right of the cursor. We also have a string c, which we call our clipboard, which starts out as empty. There are three types of actions: * The Move action. Move the cursor one step to the right. This increments ℓ once. * The Cut action. Set c ← s_right, then set s ← s_left. * The Paste action. Append the value of c to the end of the string s. Note that this doesn't modify c. The cursor initially starts at ℓ = 0. Then, we perform the following procedure: 1. Perform the Move action once. 2. Perform the Cut action once. 3. Perform the Paste action s_ℓ times. 4. If ℓ = x, stop. Otherwise, return to step 1. You're given the initial string s and the integer x. What is the length of s when the procedure stops? Since this value may be very large, only find it modulo 10^9 + 7. It is guaranteed that ℓ ≤ |s| at any time. Input The first line of input contains a single integer t (1 ≤ t ≤ 1000) denoting the number of test cases. The next lines contain descriptions of the test cases. The first line of each test case contains a single integer x (1 ≤ x ≤ 10^6). The second line of each test case consists of the initial string s (1 ≤ |s| ≤ 500). It is guaranteed, that s consists of the characters "1", "2", "3". It is guaranteed that the sum of x in a single file is at most 10^6. It is guaranteed that in each test case before the procedure will stop it will be true that ℓ ≤ |s| at any time. Output For each test case, output a single line containing a single integer denoting the answer for that test case modulo 10^9 + 7. Example Input 4 5 231 7 2323 6 333 24 133321333 Output 25 1438 1101 686531475 Note Let's illustrate what happens with the first test case. Initially, we have s = 231. Initially, ℓ = 0 and c = \varepsilon (the empty string). The following things happen if we follow the procedure above: * Step 1, Move once: we get ℓ = 1. * Step 2, Cut once: we get s = 2 and c = 31. * Step 3, Paste s_ℓ = 2 times: we get s = 23131. * Step 4: ℓ = 1 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 2. * Step 2, Cut once: we get s = 23 and c = 131. * Step 3, Paste s_ℓ = 3 times: we get s = 23131131131. * Step 4: ℓ = 2 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 3. * Step 2, Cut once: we get s = 231 and c = 31131131. * Step 3, Paste s_ℓ = 1 time: we get s = 23131131131. * Step 4: ℓ = 3 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 4. * Step 2, Cut once: we get s = 2313 and c = 1131131. * Step 3, Paste s_ℓ = 3 times: we get s = 2313113113111311311131131. * Step 4: ℓ = 4 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 5. * Step 2, Cut once: we get s = 23131 and c = 13113111311311131131. * Step 3, Paste s_ℓ = 1 times: we get s = 2313113113111311311131131. * Step 4: ℓ = 5 = x, so we stop. At the end of the procedure, s has length 25. Submitted Solution: ``` t=int(input()) for i in range(t): x=int(input()) y=input() s=[] for j in y: s.append(j) l=0 res=len(s) while(l!=x): if len(s)<x: for p in range(int(s[l])-1): for j in range(l + 1, len(s)): s.append(s[j]) res=(res+(res-l-1)*(int(s[l])-1))%(10**9+7) l+=1 print(res%(10**9+7)) ``` No
104,553
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. We start with a string s consisting only of the digits 1, 2, or 3. The length of s is denoted by |s|. For each i from 1 to |s|, the i-th character of s is denoted by s_i. There is one cursor. The cursor's location ℓ is denoted by an integer in \{0, …, |s|\}, with the following meaning: * If ℓ = 0, then the cursor is located before the first character of s. * If ℓ = |s|, then the cursor is located right after the last character of s. * If 0 < ℓ < |s|, then the cursor is located between s_ℓ and s_{ℓ+1}. We denote by s_left the string to the left of the cursor and s_right the string to the right of the cursor. We also have a string c, which we call our clipboard, which starts out as empty. There are three types of actions: * The Move action. Move the cursor one step to the right. This increments ℓ once. * The Cut action. Set c ← s_right, then set s ← s_left. * The Paste action. Append the value of c to the end of the string s. Note that this doesn't modify c. The cursor initially starts at ℓ = 0. Then, we perform the following procedure: 1. Perform the Move action once. 2. Perform the Cut action once. 3. Perform the Paste action s_ℓ times. 4. If ℓ = x, stop. Otherwise, return to step 1. You're given the initial string s and the integer x. What is the length of s when the procedure stops? Since this value may be very large, only find it modulo 10^9 + 7. It is guaranteed that ℓ ≤ |s| at any time. Input The first line of input contains a single integer t (1 ≤ t ≤ 1000) denoting the number of test cases. The next lines contain descriptions of the test cases. The first line of each test case contains a single integer x (1 ≤ x ≤ 10^6). The second line of each test case consists of the initial string s (1 ≤ |s| ≤ 500). It is guaranteed, that s consists of the characters "1", "2", "3". It is guaranteed that the sum of x in a single file is at most 10^6. It is guaranteed that in each test case before the procedure will stop it will be true that ℓ ≤ |s| at any time. Output For each test case, output a single line containing a single integer denoting the answer for that test case modulo 10^9 + 7. Example Input 4 5 231 7 2323 6 333 24 133321333 Output 25 1438 1101 686531475 Note Let's illustrate what happens with the first test case. Initially, we have s = 231. Initially, ℓ = 0 and c = \varepsilon (the empty string). The following things happen if we follow the procedure above: * Step 1, Move once: we get ℓ = 1. * Step 2, Cut once: we get s = 2 and c = 31. * Step 3, Paste s_ℓ = 2 times: we get s = 23131. * Step 4: ℓ = 1 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 2. * Step 2, Cut once: we get s = 23 and c = 131. * Step 3, Paste s_ℓ = 3 times: we get s = 23131131131. * Step 4: ℓ = 2 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 3. * Step 2, Cut once: we get s = 231 and c = 31131131. * Step 3, Paste s_ℓ = 1 time: we get s = 23131131131. * Step 4: ℓ = 3 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 4. * Step 2, Cut once: we get s = 2313 and c = 1131131. * Step 3, Paste s_ℓ = 3 times: we get s = 2313113113111311311131131. * Step 4: ℓ = 4 not= x = 5, so we return to step 1. * Step 1, Move once: we get ℓ = 5. * Step 2, Cut once: we get s = 23131 and c = 13113111311311131131. * Step 3, Paste s_ℓ = 1 times: we get s = 2313113113111311311131131. * Step 4: ℓ = 5 = x, so we stop. At the end of the procedure, s has length 25. Submitted Solution: ``` import sys import math from collections import defaultdict,Counter,deque # input=sys.stdin.readline # def print(x): # sys.stdout.write(str(x)+"\n") import os import sys from io import BytesIO, IOBase BUFSIZE = 8192 class FastIO(IOBase): newlines = 0 def __init__(self, file): self._fd = file.fileno() self.buffer = BytesIO() self.writable = "x" in file.mode or "r" not in file.mode self.write = self.buffer.write if self.writable else None def read(self): while True: b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE)) if not b: break ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines = 0 return self.buffer.read() def readline(self): while self.newlines == 0: b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE)) self.newlines = b.count(b"\n") + (not b) ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines -= 1 return self.buffer.readline() def flush(self): if self.writable: os.write(self._fd, self.buffer.getvalue()) self.buffer.truncate(0), self.buffer.seek(0) class IOWrapper(IOBase): def __init__(self, file): self.buffer = FastIO(file) self.flush = self.buffer.flush self.writable = self.buffer.writable self.write = lambda s: self.buffer.write(s.encode("ascii")) self.read = lambda: self.buffer.read().decode("ascii") self.readline = lambda: self.buffer.readline().decode("ascii") sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout) input = lambda: sys.stdin.readline().rstrip("\r\n") # sys.stdout=open("CP2/output.txt",'w') # sys.stdin=open("CP2/input.txt",'r') mod=pow(10,9)+7 t=int(input()) for i in range(t): x=int(input()) s=list(map(int,input())) cur=0 ans=0 tot=len(s)-1 while cur<x: tot=(s[cur]*tot)%mod if len(s)<x: s+=s[cur+1:]*(s[cur]-1) else: # print(len(s)) if cur+1+tot>=mod: ans=cur+1+tot-mod else: ans=cur+1+tot if tot==0: tot=10**9-1 else: tot-=1 cur+=1 print(len(s)) print(ans) ``` No
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Provide tags and a correct Python 3 solution for this coding contest problem. Ayoub thinks that he is a very smart person, so he created a function f(s), where s is a binary string (a string which contains only symbols "0" and "1"). The function f(s) is equal to the number of substrings in the string s that contains at least one symbol, that is equal to "1". More formally, f(s) is equal to the number of pairs of integers (l, r), such that 1 ≤ l ≤ r ≤ |s| (where |s| is equal to the length of string s), such that at least one of the symbols s_l, s_{l+1}, …, s_r is equal to "1". For example, if s = "01010" then f(s) = 12, because there are 12 such pairs (l, r): (1, 2), (1, 3), (1, 4), (1, 5), (2, 2), (2, 3), (2, 4), (2, 5), (3, 4), (3, 5), (4, 4), (4, 5). Ayoub also thinks that he is smarter than Mahmoud so he gave him two integers n and m and asked him this problem. For all binary strings s of length n which contains exactly m symbols equal to "1", find the maximum value of f(s). Mahmoud couldn't solve the problem so he asked you for help. Can you help him? Input The input consists of multiple test cases. The first line contains a single integer t (1 ≤ t ≤ 10^5) — the number of test cases. The description of the test cases follows. The only line for each test case contains two integers n, m (1 ≤ n ≤ 10^{9}, 0 ≤ m ≤ n) — the length of the string and the number of symbols equal to "1" in it. Output For every test case print one integer number — the maximum value of f(s) over all strings s of length n, which has exactly m symbols, equal to "1". Example Input 5 3 1 3 2 3 3 4 0 5 2 Output 4 5 6 0 12 Note In the first test case, there exists only 3 strings of length 3, which has exactly 1 symbol, equal to "1". These strings are: s_1 = "100", s_2 = "010", s_3 = "001". The values of f for them are: f(s_1) = 3, f(s_2) = 4, f(s_3) = 3, so the maximum value is 4 and the answer is 4. In the second test case, the string s with the maximum value is "101". In the third test case, the string s with the maximum value is "111". In the fourth test case, the only string s of length 4, which has exactly 0 symbols, equal to "1" is "0000" and the value of f for that string is 0, so the answer is 0. In the fifth test case, the string s with the maximum value is "01010" and it is described as an example in the problem statement. Tags: binary search, combinatorics, greedy, math, strings Correct Solution: ``` import math import sys for _ in range(int(input())): n,m=(map(int,sys.stdin.readline().split())) k=n-m p=m+1 c=(k//p) ans=(n*(n+1))//2 rem=k%p ans1=(rem*((c+1)*(c+2)))//2 ans2=0 ans2=(c*(c+1)*(p-rem))//2 print(ans-ans1-ans2) ```
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Provide tags and a correct Python 3 solution for this coding contest problem. Ayoub thinks that he is a very smart person, so he created a function f(s), where s is a binary string (a string which contains only symbols "0" and "1"). The function f(s) is equal to the number of substrings in the string s that contains at least one symbol, that is equal to "1". More formally, f(s) is equal to the number of pairs of integers (l, r), such that 1 ≤ l ≤ r ≤ |s| (where |s| is equal to the length of string s), such that at least one of the symbols s_l, s_{l+1}, …, s_r is equal to "1". For example, if s = "01010" then f(s) = 12, because there are 12 such pairs (l, r): (1, 2), (1, 3), (1, 4), (1, 5), (2, 2), (2, 3), (2, 4), (2, 5), (3, 4), (3, 5), (4, 4), (4, 5). Ayoub also thinks that he is smarter than Mahmoud so he gave him two integers n and m and asked him this problem. For all binary strings s of length n which contains exactly m symbols equal to "1", find the maximum value of f(s). Mahmoud couldn't solve the problem so he asked you for help. Can you help him? Input The input consists of multiple test cases. The first line contains a single integer t (1 ≤ t ≤ 10^5) — the number of test cases. The description of the test cases follows. The only line for each test case contains two integers n, m (1 ≤ n ≤ 10^{9}, 0 ≤ m ≤ n) — the length of the string and the number of symbols equal to "1" in it. Output For every test case print one integer number — the maximum value of f(s) over all strings s of length n, which has exactly m symbols, equal to "1". Example Input 5 3 1 3 2 3 3 4 0 5 2 Output 4 5 6 0 12 Note In the first test case, there exists only 3 strings of length 3, which has exactly 1 symbol, equal to "1". These strings are: s_1 = "100", s_2 = "010", s_3 = "001". The values of f for them are: f(s_1) = 3, f(s_2) = 4, f(s_3) = 3, so the maximum value is 4 and the answer is 4. In the second test case, the string s with the maximum value is "101". In the third test case, the string s with the maximum value is "111". In the fourth test case, the only string s of length 4, which has exactly 0 symbols, equal to "1" is "0000" and the value of f for that string is 0, so the answer is 0. In the fifth test case, the string s with the maximum value is "01010" and it is described as an example in the problem statement. Tags: binary search, combinatorics, greedy, math, strings Correct Solution: ``` import sys input = sys.stdin.readline t = int(input()) C = [list(map(int,input().split())) for i in range(t)] # ANS = [0] * t # t = 10**5 # C = [[523422132331, 102342223434] for i in range(t)] def c(x, y): if x % 2 == 0: return (x//2) * y else: return (y//2) * x for i in range(t): n = C[i][0] o = C[i][1] z = n-o al = c(n, (n-1)) + n # print("al",al) if z-1 <= o: print(al - z) # ANS[i] = al-z # v=0 else: a = z // (o+1) b = z % (o+1) # print(a,b) mi = c((a+1), (a+2)) * b + c(a, (a+1)) * (o+1-b) print(al - mi) # ANS[i] = al-mi # for i in ANS: # print(i) ```
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Provide tags and a correct Python 3 solution for this coding contest problem. Ayoub thinks that he is a very smart person, so he created a function f(s), where s is a binary string (a string which contains only symbols "0" and "1"). The function f(s) is equal to the number of substrings in the string s that contains at least one symbol, that is equal to "1". More formally, f(s) is equal to the number of pairs of integers (l, r), such that 1 ≤ l ≤ r ≤ |s| (where |s| is equal to the length of string s), such that at least one of the symbols s_l, s_{l+1}, …, s_r is equal to "1". For example, if s = "01010" then f(s) = 12, because there are 12 such pairs (l, r): (1, 2), (1, 3), (1, 4), (1, 5), (2, 2), (2, 3), (2, 4), (2, 5), (3, 4), (3, 5), (4, 4), (4, 5). Ayoub also thinks that he is smarter than Mahmoud so he gave him two integers n and m and asked him this problem. For all binary strings s of length n which contains exactly m symbols equal to "1", find the maximum value of f(s). Mahmoud couldn't solve the problem so he asked you for help. Can you help him? Input The input consists of multiple test cases. The first line contains a single integer t (1 ≤ t ≤ 10^5) — the number of test cases. The description of the test cases follows. The only line for each test case contains two integers n, m (1 ≤ n ≤ 10^{9}, 0 ≤ m ≤ n) — the length of the string and the number of symbols equal to "1" in it. Output For every test case print one integer number — the maximum value of f(s) over all strings s of length n, which has exactly m symbols, equal to "1". Example Input 5 3 1 3 2 3 3 4 0 5 2 Output 4 5 6 0 12 Note In the first test case, there exists only 3 strings of length 3, which has exactly 1 symbol, equal to "1". These strings are: s_1 = "100", s_2 = "010", s_3 = "001". The values of f for them are: f(s_1) = 3, f(s_2) = 4, f(s_3) = 3, so the maximum value is 4 and the answer is 4. In the second test case, the string s with the maximum value is "101". In the third test case, the string s with the maximum value is "111". In the fourth test case, the only string s of length 4, which has exactly 0 symbols, equal to "1" is "0000" and the value of f for that string is 0, so the answer is 0. In the fifth test case, the string s with the maximum value is "01010" and it is described as an example in the problem statement. Tags: binary search, combinatorics, greedy, math, strings Correct Solution: ``` import sys input=sys.stdin.readline for _ in range(int(input())): n,m=map(int,input().split()) grps=m+1 zeach=(n-m)//grps extras=(n-m)%grps print( (n*(n+1)//2)- (zeach*(zeach+1)//2)*grps -(extras)*(zeach+1) ) ```
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Provide tags and a correct Python 3 solution for this coding contest problem. Ayoub thinks that he is a very smart person, so he created a function f(s), where s is a binary string (a string which contains only symbols "0" and "1"). The function f(s) is equal to the number of substrings in the string s that contains at least one symbol, that is equal to "1". More formally, f(s) is equal to the number of pairs of integers (l, r), such that 1 ≤ l ≤ r ≤ |s| (where |s| is equal to the length of string s), such that at least one of the symbols s_l, s_{l+1}, …, s_r is equal to "1". For example, if s = "01010" then f(s) = 12, because there are 12 such pairs (l, r): (1, 2), (1, 3), (1, 4), (1, 5), (2, 2), (2, 3), (2, 4), (2, 5), (3, 4), (3, 5), (4, 4), (4, 5). Ayoub also thinks that he is smarter than Mahmoud so he gave him two integers n and m and asked him this problem. For all binary strings s of length n which contains exactly m symbols equal to "1", find the maximum value of f(s). Mahmoud couldn't solve the problem so he asked you for help. Can you help him? Input The input consists of multiple test cases. The first line contains a single integer t (1 ≤ t ≤ 10^5) — the number of test cases. The description of the test cases follows. The only line for each test case contains two integers n, m (1 ≤ n ≤ 10^{9}, 0 ≤ m ≤ n) — the length of the string and the number of symbols equal to "1" in it. Output For every test case print one integer number — the maximum value of f(s) over all strings s of length n, which has exactly m symbols, equal to "1". Example Input 5 3 1 3 2 3 3 4 0 5 2 Output 4 5 6 0 12 Note In the first test case, there exists only 3 strings of length 3, which has exactly 1 symbol, equal to "1". These strings are: s_1 = "100", s_2 = "010", s_3 = "001". The values of f for them are: f(s_1) = 3, f(s_2) = 4, f(s_3) = 3, so the maximum value is 4 and the answer is 4. In the second test case, the string s with the maximum value is "101". In the third test case, the string s with the maximum value is "111". In the fourth test case, the only string s of length 4, which has exactly 0 symbols, equal to "1" is "0000" and the value of f for that string is 0, so the answer is 0. In the fifth test case, the string s with the maximum value is "01010" and it is described as an example in the problem statement. Tags: binary search, combinatorics, greedy, math, strings Correct Solution: ``` import os import sys from io import BytesIO, IOBase from collections import Counter BUFSIZE = 8192 class FastIO(IOBase): newlines = 0 def __init__(self, file): self._fd = file.fileno() self.buffer = BytesIO() self.writable = "x" in file.mode or "r" not in file.mode self.write = self.buffer.write if self.writable else None def read(self): while True: b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE)) if not b: break ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines = 0 return self.buffer.read() def readline(self): while self.newlines == 0: b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE)) self.newlines = b.count(b"\n") + (not b) ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines -= 1 return self.buffer.readline() def flush(self): if self.writable: os.write(self._fd, self.buffer.getvalue()) self.buffer.truncate(0), self.buffer.seek(0) class IOWrapper(IOBase): def __init__(self, file): self.buffer = FastIO(file) self.flush = self.buffer.flush self.writable = self.buffer.writable self.write = lambda s: self.buffer.write(s.encode("ascii")) self.read = lambda: self.buffer.read().decode("ascii") self.readline = lambda: self.buffer.readline().decode("ascii") sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout) def gcd(a, b): if a == 0: return b return gcd(b % a, a) def lcm(a, b): return (a * b) / gcd(a, b) def main(): for _ in range(int(input())): n,m=map(int, input().split()) ans=n*(n+1)//2 #print(ans) k=(n-m)//(m+1) f=k k=(n-m)%(m+1) ans-=(m+1-k)*(f*(f+1)//2) #print(ans) f+=1 ans-=(k)*(f*(f+1)//2) print(ans) return if __name__ == "__main__": main() ```
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Provide tags and a correct Python 3 solution for this coding contest problem. Ayoub thinks that he is a very smart person, so he created a function f(s), where s is a binary string (a string which contains only symbols "0" and "1"). The function f(s) is equal to the number of substrings in the string s that contains at least one symbol, that is equal to "1". More formally, f(s) is equal to the number of pairs of integers (l, r), such that 1 ≤ l ≤ r ≤ |s| (where |s| is equal to the length of string s), such that at least one of the symbols s_l, s_{l+1}, …, s_r is equal to "1". For example, if s = "01010" then f(s) = 12, because there are 12 such pairs (l, r): (1, 2), (1, 3), (1, 4), (1, 5), (2, 2), (2, 3), (2, 4), (2, 5), (3, 4), (3, 5), (4, 4), (4, 5). Ayoub also thinks that he is smarter than Mahmoud so he gave him two integers n and m and asked him this problem. For all binary strings s of length n which contains exactly m symbols equal to "1", find the maximum value of f(s). Mahmoud couldn't solve the problem so he asked you for help. Can you help him? Input The input consists of multiple test cases. The first line contains a single integer t (1 ≤ t ≤ 10^5) — the number of test cases. The description of the test cases follows. The only line for each test case contains two integers n, m (1 ≤ n ≤ 10^{9}, 0 ≤ m ≤ n) — the length of the string and the number of symbols equal to "1" in it. Output For every test case print one integer number — the maximum value of f(s) over all strings s of length n, which has exactly m symbols, equal to "1". Example Input 5 3 1 3 2 3 3 4 0 5 2 Output 4 5 6 0 12 Note In the first test case, there exists only 3 strings of length 3, which has exactly 1 symbol, equal to "1". These strings are: s_1 = "100", s_2 = "010", s_3 = "001". The values of f for them are: f(s_1) = 3, f(s_2) = 4, f(s_3) = 3, so the maximum value is 4 and the answer is 4. In the second test case, the string s with the maximum value is "101". In the third test case, the string s with the maximum value is "111". In the fourth test case, the only string s of length 4, which has exactly 0 symbols, equal to "1" is "0000" and the value of f for that string is 0, so the answer is 0. In the fifth test case, the string s with the maximum value is "01010" and it is described as an example in the problem statement. Tags: binary search, combinatorics, greedy, math, strings Correct Solution: ``` import sys input = sys.stdin.readline T = int(input()) for _ in range(T): n, m = list(map(int, input().split())) S = 0 x = (n - m) // (m + 1) z = (n - m) % (m + 1) S += (m + 1 - z) * (x * (x + 1)) // 2 S += z * (x + 1) * (x + 2) // 2 print(n * (n + 1) // 2 - S) ```
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Provide tags and a correct Python 3 solution for this coding contest problem. Ayoub thinks that he is a very smart person, so he created a function f(s), where s is a binary string (a string which contains only symbols "0" and "1"). The function f(s) is equal to the number of substrings in the string s that contains at least one symbol, that is equal to "1". More formally, f(s) is equal to the number of pairs of integers (l, r), such that 1 ≤ l ≤ r ≤ |s| (where |s| is equal to the length of string s), such that at least one of the symbols s_l, s_{l+1}, …, s_r is equal to "1". For example, if s = "01010" then f(s) = 12, because there are 12 such pairs (l, r): (1, 2), (1, 3), (1, 4), (1, 5), (2, 2), (2, 3), (2, 4), (2, 5), (3, 4), (3, 5), (4, 4), (4, 5). Ayoub also thinks that he is smarter than Mahmoud so he gave him two integers n and m and asked him this problem. For all binary strings s of length n which contains exactly m symbols equal to "1", find the maximum value of f(s). Mahmoud couldn't solve the problem so he asked you for help. Can you help him? Input The input consists of multiple test cases. The first line contains a single integer t (1 ≤ t ≤ 10^5) — the number of test cases. The description of the test cases follows. The only line for each test case contains two integers n, m (1 ≤ n ≤ 10^{9}, 0 ≤ m ≤ n) — the length of the string and the number of symbols equal to "1" in it. Output For every test case print one integer number — the maximum value of f(s) over all strings s of length n, which has exactly m symbols, equal to "1". Example Input 5 3 1 3 2 3 3 4 0 5 2 Output 4 5 6 0 12 Note In the first test case, there exists only 3 strings of length 3, which has exactly 1 symbol, equal to "1". These strings are: s_1 = "100", s_2 = "010", s_3 = "001". The values of f for them are: f(s_1) = 3, f(s_2) = 4, f(s_3) = 3, so the maximum value is 4 and the answer is 4. In the second test case, the string s with the maximum value is "101". In the third test case, the string s with the maximum value is "111". In the fourth test case, the only string s of length 4, which has exactly 0 symbols, equal to "1" is "0000" and the value of f for that string is 0, so the answer is 0. In the fifth test case, the string s with the maximum value is "01010" and it is described as an example in the problem statement. Tags: binary search, combinatorics, greedy, math, strings Correct Solution: ``` """ // Author : snape_here - Susanta Mukherjee """ from __future__ import division, print_function import os,sys from io import BytesIO, IOBase if sys.version_info[0] < 3: from __builtin__ import xrange as range from future_builtins import ascii, filter, hex, map, oct, zip def ii(): return int(input()) def si(): return input() def mi(): return map(int,input().split()) def li(): return list(mi()) def gcd(x, y): while y: x, y = y, x % y return x def read(): sys.stdin = open('input.txt', 'r') sys.stdout = open('output.txt', 'w') import math mod=1000000007 def day(d, m, y): t = [ 0, 3, 2, 5, 0, 3, 5, 1, 4, 6, 2, 4 ] y -= m < 3 return (( y + int(y / 4) - int(y / 100) + int(y / 400) + t[m - 1] + d) % 7) def isl(y): if y%400==0: return True elif y%4==0 and y%100!=0: return True return False def main(): for i in range(ii()): n,m=mi() if m==0: ans=0 else: tot=(n*(n+1))//2 s=(n-m)//(m+1) b=(m+1-(n-m)%(m+1))*s*(s+1)//2 + ((n-m)%(m+1))*(s+1)*(s+2)//2 ans=tot-b print(ans) # region fastio# BUFSIZE = 8192 class FastIO(IOBase): newlines = 0 def __init__(self, file): self._fd = file.fileno() self.buffer = BytesIO() self.writable = "x" in file.mode or "r" not in file.mode self.write = self.buffer.write if self.writable else None def read(self): while True: b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE)) if not b: break ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines = 0 return self.buffer.read() def readline(self): while self.newlines == 0: b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE)) self.newlines = b.count(b"\n") + (not b) ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines -= 1 return self.buffer.readline() def flush(self): if self.writable: os.write(self._fd, self.buffer.getvalue()) self.buffer.truncate(0), self.buffer.seek(0) class IOWrapper(IOBase): def __init__(self, file): self.buffer = FastIO(file) self.flush = self.buffer.flush self.writable = self.buffer.writable self.write = lambda s: self.buffer.write(s.encode("ascii")) self.read = lambda: self.buffer.read().decode("ascii") self.readline = lambda: self.buffer.readline().decode("ascii") def print(*args, **kwargs): """Prints the values to a stream, or to sys.stdout by default.""" sep, file = kwargs.pop("sep", " "), kwargs.pop("file", sys.stdout) at_start = True for x in args: if not at_start: file.write(sep) file.write(str(x)) at_start = False file.write(kwargs.pop("end", "\n")) if kwargs.pop("flush", False): file.flush() if sys.version_info[0] < 3: sys.stdin, sys.stdout = FastIO(sys.stdin), FastIO(sys.stdout) else: sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout) input = lambda: sys.stdin.readline().rstrip("\r\n") # endregion if __name__ == "__main__": #read() main() #Comment read() ```
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Provide tags and a correct Python 3 solution for this coding contest problem. Ayoub thinks that he is a very smart person, so he created a function f(s), where s is a binary string (a string which contains only symbols "0" and "1"). The function f(s) is equal to the number of substrings in the string s that contains at least one symbol, that is equal to "1". More formally, f(s) is equal to the number of pairs of integers (l, r), such that 1 ≤ l ≤ r ≤ |s| (where |s| is equal to the length of string s), such that at least one of the symbols s_l, s_{l+1}, …, s_r is equal to "1". For example, if s = "01010" then f(s) = 12, because there are 12 such pairs (l, r): (1, 2), (1, 3), (1, 4), (1, 5), (2, 2), (2, 3), (2, 4), (2, 5), (3, 4), (3, 5), (4, 4), (4, 5). Ayoub also thinks that he is smarter than Mahmoud so he gave him two integers n and m and asked him this problem. For all binary strings s of length n which contains exactly m symbols equal to "1", find the maximum value of f(s). Mahmoud couldn't solve the problem so he asked you for help. Can you help him? Input The input consists of multiple test cases. The first line contains a single integer t (1 ≤ t ≤ 10^5) — the number of test cases. The description of the test cases follows. The only line for each test case contains two integers n, m (1 ≤ n ≤ 10^{9}, 0 ≤ m ≤ n) — the length of the string and the number of symbols equal to "1" in it. Output For every test case print one integer number — the maximum value of f(s) over all strings s of length n, which has exactly m symbols, equal to "1". Example Input 5 3 1 3 2 3 3 4 0 5 2 Output 4 5 6 0 12 Note In the first test case, there exists only 3 strings of length 3, which has exactly 1 symbol, equal to "1". These strings are: s_1 = "100", s_2 = "010", s_3 = "001". The values of f for them are: f(s_1) = 3, f(s_2) = 4, f(s_3) = 3, so the maximum value is 4 and the answer is 4. In the second test case, the string s with the maximum value is "101". In the third test case, the string s with the maximum value is "111". In the fourth test case, the only string s of length 4, which has exactly 0 symbols, equal to "1" is "0000" and the value of f for that string is 0, so the answer is 0. In the fifth test case, the string s with the maximum value is "01010" and it is described as an example in the problem statement. Tags: binary search, combinatorics, greedy, math, strings Correct Solution: ``` import sys inf = 1 << 64 def input(): return sys.stdin.readline().rstrip() def slv(): n, m = map(int, input().split()) u, v = divmod(n - m, m + 1) ans = n * (n + 1)//2 - v*(u + 1)*(u + 2)//2 - (m + 1 - v)*u*(u + 1)//2 print(ans) return t = int(input()) for i in range(t): slv() ```
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Provide tags and a correct Python 3 solution for this coding contest problem. Ayoub thinks that he is a very smart person, so he created a function f(s), where s is a binary string (a string which contains only symbols "0" and "1"). The function f(s) is equal to the number of substrings in the string s that contains at least one symbol, that is equal to "1". More formally, f(s) is equal to the number of pairs of integers (l, r), such that 1 ≤ l ≤ r ≤ |s| (where |s| is equal to the length of string s), such that at least one of the symbols s_l, s_{l+1}, …, s_r is equal to "1". For example, if s = "01010" then f(s) = 12, because there are 12 such pairs (l, r): (1, 2), (1, 3), (1, 4), (1, 5), (2, 2), (2, 3), (2, 4), (2, 5), (3, 4), (3, 5), (4, 4), (4, 5). Ayoub also thinks that he is smarter than Mahmoud so he gave him two integers n and m and asked him this problem. For all binary strings s of length n which contains exactly m symbols equal to "1", find the maximum value of f(s). Mahmoud couldn't solve the problem so he asked you for help. Can you help him? Input The input consists of multiple test cases. The first line contains a single integer t (1 ≤ t ≤ 10^5) — the number of test cases. The description of the test cases follows. The only line for each test case contains two integers n, m (1 ≤ n ≤ 10^{9}, 0 ≤ m ≤ n) — the length of the string and the number of symbols equal to "1" in it. Output For every test case print one integer number — the maximum value of f(s) over all strings s of length n, which has exactly m symbols, equal to "1". Example Input 5 3 1 3 2 3 3 4 0 5 2 Output 4 5 6 0 12 Note In the first test case, there exists only 3 strings of length 3, which has exactly 1 symbol, equal to "1". These strings are: s_1 = "100", s_2 = "010", s_3 = "001". The values of f for them are: f(s_1) = 3, f(s_2) = 4, f(s_3) = 3, so the maximum value is 4 and the answer is 4. In the second test case, the string s with the maximum value is "101". In the third test case, the string s with the maximum value is "111". In the fourth test case, the only string s of length 4, which has exactly 0 symbols, equal to "1" is "0000" and the value of f for that string is 0, so the answer is 0. In the fifth test case, the string s with the maximum value is "01010" and it is described as an example in the problem statement. Tags: binary search, combinatorics, greedy, math, strings Correct Solution: ``` import sys input=sys.stdin.readline t=int(input()) for i in range(t): n,m=map(int,input().split()) zeros=n-m if zeros==0: print((n*(n+1))//2) else: div=zeros//(m+1) rem=zeros%(m+1) print(n*(n+1)//2-rem*(div+1)*(div+2)//2-(m+1-rem)*((div+1)*div)//2) ```
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Ayoub thinks that he is a very smart person, so he created a function f(s), where s is a binary string (a string which contains only symbols "0" and "1"). The function f(s) is equal to the number of substrings in the string s that contains at least one symbol, that is equal to "1". More formally, f(s) is equal to the number of pairs of integers (l, r), such that 1 ≤ l ≤ r ≤ |s| (where |s| is equal to the length of string s), such that at least one of the symbols s_l, s_{l+1}, …, s_r is equal to "1". For example, if s = "01010" then f(s) = 12, because there are 12 such pairs (l, r): (1, 2), (1, 3), (1, 4), (1, 5), (2, 2), (2, 3), (2, 4), (2, 5), (3, 4), (3, 5), (4, 4), (4, 5). Ayoub also thinks that he is smarter than Mahmoud so he gave him two integers n and m and asked him this problem. For all binary strings s of length n which contains exactly m symbols equal to "1", find the maximum value of f(s). Mahmoud couldn't solve the problem so he asked you for help. Can you help him? Input The input consists of multiple test cases. The first line contains a single integer t (1 ≤ t ≤ 10^5) — the number of test cases. The description of the test cases follows. The only line for each test case contains two integers n, m (1 ≤ n ≤ 10^{9}, 0 ≤ m ≤ n) — the length of the string and the number of symbols equal to "1" in it. Output For every test case print one integer number — the maximum value of f(s) over all strings s of length n, which has exactly m symbols, equal to "1". Example Input 5 3 1 3 2 3 3 4 0 5 2 Output 4 5 6 0 12 Note In the first test case, there exists only 3 strings of length 3, which has exactly 1 symbol, equal to "1". These strings are: s_1 = "100", s_2 = "010", s_3 = "001". The values of f for them are: f(s_1) = 3, f(s_2) = 4, f(s_3) = 3, so the maximum value is 4 and the answer is 4. In the second test case, the string s with the maximum value is "101". In the third test case, the string s with the maximum value is "111". In the fourth test case, the only string s of length 4, which has exactly 0 symbols, equal to "1" is "0000" and the value of f for that string is 0, so the answer is 0. In the fifth test case, the string s with the maximum value is "01010" and it is described as an example in the problem statement. Submitted Solution: ``` from sys import stdin, stdout def total(k): return (k*(k+1)) // 2 ans = [] t= int(stdin.readline()) for line in stdin: n, m = tuple(map(int,line.split())) if m==0: ans.append( str(0) ) else: al = total(n) zeros = n-m #divide into m+1 groups k, extra = zeros//(m+1), zeros%(m+1) zero_blocks = extra*(k+1) + (m+1)*total(k) ans.append(str(al-zero_blocks)) stdout.write('\n'.join(ans)) ``` Yes
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Ayoub thinks that he is a very smart person, so he created a function f(s), where s is a binary string (a string which contains only symbols "0" and "1"). The function f(s) is equal to the number of substrings in the string s that contains at least one symbol, that is equal to "1". More formally, f(s) is equal to the number of pairs of integers (l, r), such that 1 ≤ l ≤ r ≤ |s| (where |s| is equal to the length of string s), such that at least one of the symbols s_l, s_{l+1}, …, s_r is equal to "1". For example, if s = "01010" then f(s) = 12, because there are 12 such pairs (l, r): (1, 2), (1, 3), (1, 4), (1, 5), (2, 2), (2, 3), (2, 4), (2, 5), (3, 4), (3, 5), (4, 4), (4, 5). Ayoub also thinks that he is smarter than Mahmoud so he gave him two integers n and m and asked him this problem. For all binary strings s of length n which contains exactly m symbols equal to "1", find the maximum value of f(s). Mahmoud couldn't solve the problem so he asked you for help. Can you help him? Input The input consists of multiple test cases. The first line contains a single integer t (1 ≤ t ≤ 10^5) — the number of test cases. The description of the test cases follows. The only line for each test case contains two integers n, m (1 ≤ n ≤ 10^{9}, 0 ≤ m ≤ n) — the length of the string and the number of symbols equal to "1" in it. Output For every test case print one integer number — the maximum value of f(s) over all strings s of length n, which has exactly m symbols, equal to "1". Example Input 5 3 1 3 2 3 3 4 0 5 2 Output 4 5 6 0 12 Note In the first test case, there exists only 3 strings of length 3, which has exactly 1 symbol, equal to "1". These strings are: s_1 = "100", s_2 = "010", s_3 = "001". The values of f for them are: f(s_1) = 3, f(s_2) = 4, f(s_3) = 3, so the maximum value is 4 and the answer is 4. In the second test case, the string s with the maximum value is "101". In the third test case, the string s with the maximum value is "111". In the fourth test case, the only string s of length 4, which has exactly 0 symbols, equal to "1" is "0000" and the value of f for that string is 0, so the answer is 0. In the fifth test case, the string s with the maximum value is "01010" and it is described as an example in the problem statement. Submitted Solution: ``` import sys lines = list(sys.stdin.readlines()) t = int(lines[0]) def count(x): return x * (x+1)//2 for i in range(t): n, ones = map(int, lines[i+1].split()) zeros = n - ones if zeros==0: print(count(n)) continue used_ones = min(ones, zeros-1) groups = used_ones+1 smal_size = zeros//groups larg_size = smal_size + 1 larg_count = zeros%groups total = count(n) total -= count(smal_size) * (groups-larg_count) total -= count(larg_size) * larg_count print(total) ``` Yes
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Ayoub thinks that he is a very smart person, so he created a function f(s), where s is a binary string (a string which contains only symbols "0" and "1"). The function f(s) is equal to the number of substrings in the string s that contains at least one symbol, that is equal to "1". More formally, f(s) is equal to the number of pairs of integers (l, r), such that 1 ≤ l ≤ r ≤ |s| (where |s| is equal to the length of string s), such that at least one of the symbols s_l, s_{l+1}, …, s_r is equal to "1". For example, if s = "01010" then f(s) = 12, because there are 12 such pairs (l, r): (1, 2), (1, 3), (1, 4), (1, 5), (2, 2), (2, 3), (2, 4), (2, 5), (3, 4), (3, 5), (4, 4), (4, 5). Ayoub also thinks that he is smarter than Mahmoud so he gave him two integers n and m and asked him this problem. For all binary strings s of length n which contains exactly m symbols equal to "1", find the maximum value of f(s). Mahmoud couldn't solve the problem so he asked you for help. Can you help him? Input The input consists of multiple test cases. The first line contains a single integer t (1 ≤ t ≤ 10^5) — the number of test cases. The description of the test cases follows. The only line for each test case contains two integers n, m (1 ≤ n ≤ 10^{9}, 0 ≤ m ≤ n) — the length of the string and the number of symbols equal to "1" in it. Output For every test case print one integer number — the maximum value of f(s) over all strings s of length n, which has exactly m symbols, equal to "1". Example Input 5 3 1 3 2 3 3 4 0 5 2 Output 4 5 6 0 12 Note In the first test case, there exists only 3 strings of length 3, which has exactly 1 symbol, equal to "1". These strings are: s_1 = "100", s_2 = "010", s_3 = "001". The values of f for them are: f(s_1) = 3, f(s_2) = 4, f(s_3) = 3, so the maximum value is 4 and the answer is 4. In the second test case, the string s with the maximum value is "101". In the third test case, the string s with the maximum value is "111". In the fourth test case, the only string s of length 4, which has exactly 0 symbols, equal to "1" is "0000" and the value of f for that string is 0, so the answer is 0. In the fifth test case, the string s with the maximum value is "01010" and it is described as an example in the problem statement. Submitted Solution: ``` import sys def fastio(): from io import StringIO from atexit import register global input sys.stdin = StringIO(sys.stdin.read()) input = lambda : sys.stdin.readline().rstrip('\r\n') sys.stdout = StringIO() register(lambda : sys.__stdout__.write(sys.stdout.getvalue())) fastio() for _ in range(int(input())): n,m=list(map(int,input().split())) l=n if m==0 else (n-2*m if m<=n//2 else 0) s1=n-m-l if l==n: print(0) else: p=(n-m)//(m+1);r=(n-m)%(m+1) k=(n*(n+1))//2-(m+1-r)*(p*(p+1)//2)-r*(p+1)*(p+2)//2 print(k) ``` Yes
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Ayoub thinks that he is a very smart person, so he created a function f(s), where s is a binary string (a string which contains only symbols "0" and "1"). The function f(s) is equal to the number of substrings in the string s that contains at least one symbol, that is equal to "1". More formally, f(s) is equal to the number of pairs of integers (l, r), such that 1 ≤ l ≤ r ≤ |s| (where |s| is equal to the length of string s), such that at least one of the symbols s_l, s_{l+1}, …, s_r is equal to "1". For example, if s = "01010" then f(s) = 12, because there are 12 such pairs (l, r): (1, 2), (1, 3), (1, 4), (1, 5), (2, 2), (2, 3), (2, 4), (2, 5), (3, 4), (3, 5), (4, 4), (4, 5). Ayoub also thinks that he is smarter than Mahmoud so he gave him two integers n and m and asked him this problem. For all binary strings s of length n which contains exactly m symbols equal to "1", find the maximum value of f(s). Mahmoud couldn't solve the problem so he asked you for help. Can you help him? Input The input consists of multiple test cases. The first line contains a single integer t (1 ≤ t ≤ 10^5) — the number of test cases. The description of the test cases follows. The only line for each test case contains two integers n, m (1 ≤ n ≤ 10^{9}, 0 ≤ m ≤ n) — the length of the string and the number of symbols equal to "1" in it. Output For every test case print one integer number — the maximum value of f(s) over all strings s of length n, which has exactly m symbols, equal to "1". Example Input 5 3 1 3 2 3 3 4 0 5 2 Output 4 5 6 0 12 Note In the first test case, there exists only 3 strings of length 3, which has exactly 1 symbol, equal to "1". These strings are: s_1 = "100", s_2 = "010", s_3 = "001". The values of f for them are: f(s_1) = 3, f(s_2) = 4, f(s_3) = 3, so the maximum value is 4 and the answer is 4. In the second test case, the string s with the maximum value is "101". In the third test case, the string s with the maximum value is "111". In the fourth test case, the only string s of length 4, which has exactly 0 symbols, equal to "1" is "0000" and the value of f for that string is 0, so the answer is 0. In the fifth test case, the string s with the maximum value is "01010" and it is described as an example in the problem statement. Submitted Solution: ``` # import sys # import math # from collections import defaultdict,Counter # input=sys.stdin.readline # def print(x): # sys.stdout.write(str(x)+"\n") import os import sys from io import BytesIO, IOBase BUFSIZE = 8192 class FastIO(IOBase): newlines = 0 def __init__(self, file): self._fd = file.fileno() self.buffer = BytesIO() self.writable = "x" in file.mode or "r" not in file.mode self.write = self.buffer.write if self.writable else None def read(self): while True: b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE)) if not b: break ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines = 0 return self.buffer.read() def readline(self): while self.newlines == 0: b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE)) self.newlines = b.count(b"\n") + (not b) ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines -= 1 return self.buffer.readline() def flush(self): if self.writable: os.write(self._fd, self.buffer.getvalue()) self.buffer.truncate(0), self.buffer.seek(0) class IOWrapper(IOBase): def __init__(self, file): self.buffer = FastIO(file) self.flush = self.buffer.flush self.writable = self.buffer.writable self.write = lambda s: self.buffer.write(s.encode("ascii")) self.read = lambda: self.buffer.read().decode("ascii") self.readline = lambda: self.buffer.readline().decode("ascii") sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout) input = lambda: sys.stdin.readline().rstrip("\r\n") # sys.stdout=open("CP3/output.txt",'w') # sys.stdin=open("CP3/input.txt",'r') # m=pow(10,9)+7 t=int(input()) for i in range(t): n,m=map(int,input().split()) if m==0: print(0) elif n-m<=m: print(n*(n+1)//2-(n-m)) else: d=n-m k=d//(m+1) d1=d%(m+1) print(n*(n+1)//2-(m+1)*(k*(k+1)//2)-(k+1)*d1) ``` Yes
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Ayoub thinks that he is a very smart person, so he created a function f(s), where s is a binary string (a string which contains only symbols "0" and "1"). The function f(s) is equal to the number of substrings in the string s that contains at least one symbol, that is equal to "1". More formally, f(s) is equal to the number of pairs of integers (l, r), such that 1 ≤ l ≤ r ≤ |s| (where |s| is equal to the length of string s), such that at least one of the symbols s_l, s_{l+1}, …, s_r is equal to "1". For example, if s = "01010" then f(s) = 12, because there are 12 such pairs (l, r): (1, 2), (1, 3), (1, 4), (1, 5), (2, 2), (2, 3), (2, 4), (2, 5), (3, 4), (3, 5), (4, 4), (4, 5). Ayoub also thinks that he is smarter than Mahmoud so he gave him two integers n and m and asked him this problem. For all binary strings s of length n which contains exactly m symbols equal to "1", find the maximum value of f(s). Mahmoud couldn't solve the problem so he asked you for help. Can you help him? Input The input consists of multiple test cases. The first line contains a single integer t (1 ≤ t ≤ 10^5) — the number of test cases. The description of the test cases follows. The only line for each test case contains two integers n, m (1 ≤ n ≤ 10^{9}, 0 ≤ m ≤ n) — the length of the string and the number of symbols equal to "1" in it. Output For every test case print one integer number — the maximum value of f(s) over all strings s of length n, which has exactly m symbols, equal to "1". Example Input 5 3 1 3 2 3 3 4 0 5 2 Output 4 5 6 0 12 Note In the first test case, there exists only 3 strings of length 3, which has exactly 1 symbol, equal to "1". These strings are: s_1 = "100", s_2 = "010", s_3 = "001". The values of f for them are: f(s_1) = 3, f(s_2) = 4, f(s_3) = 3, so the maximum value is 4 and the answer is 4. In the second test case, the string s with the maximum value is "101". In the third test case, the string s with the maximum value is "111". In the fourth test case, the only string s of length 4, which has exactly 0 symbols, equal to "1" is "0000" and the value of f for that string is 0, so the answer is 0. In the fifth test case, the string s with the maximum value is "01010" and it is described as an example in the problem statement. Submitted Solution: ``` import math def main(): num = int(input()) for _ in range(num): n, m = map(int, input().split()) if m == 0: print(0) continue b = n - m a = n // 2 if m == 1: d = math.ceil(n/2) ans = d ** 2 elif a < b: ans = n * (n + 1) // 2 d = math.ceil(n/2) amari = m - d ans -= amari * (amari + 1) * 2 + d else: ans = n * (n + 1) // 2 ans -= b print(ans) main() ``` No
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Ayoub thinks that he is a very smart person, so he created a function f(s), where s is a binary string (a string which contains only symbols "0" and "1"). The function f(s) is equal to the number of substrings in the string s that contains at least one symbol, that is equal to "1". More formally, f(s) is equal to the number of pairs of integers (l, r), such that 1 ≤ l ≤ r ≤ |s| (where |s| is equal to the length of string s), such that at least one of the symbols s_l, s_{l+1}, …, s_r is equal to "1". For example, if s = "01010" then f(s) = 12, because there are 12 such pairs (l, r): (1, 2), (1, 3), (1, 4), (1, 5), (2, 2), (2, 3), (2, 4), (2, 5), (3, 4), (3, 5), (4, 4), (4, 5). Ayoub also thinks that he is smarter than Mahmoud so he gave him two integers n and m and asked him this problem. For all binary strings s of length n which contains exactly m symbols equal to "1", find the maximum value of f(s). Mahmoud couldn't solve the problem so he asked you for help. Can you help him? Input The input consists of multiple test cases. The first line contains a single integer t (1 ≤ t ≤ 10^5) — the number of test cases. The description of the test cases follows. The only line for each test case contains two integers n, m (1 ≤ n ≤ 10^{9}, 0 ≤ m ≤ n) — the length of the string and the number of symbols equal to "1" in it. Output For every test case print one integer number — the maximum value of f(s) over all strings s of length n, which has exactly m symbols, equal to "1". Example Input 5 3 1 3 2 3 3 4 0 5 2 Output 4 5 6 0 12 Note In the first test case, there exists only 3 strings of length 3, which has exactly 1 symbol, equal to "1". These strings are: s_1 = "100", s_2 = "010", s_3 = "001". The values of f for them are: f(s_1) = 3, f(s_2) = 4, f(s_3) = 3, so the maximum value is 4 and the answer is 4. In the second test case, the string s with the maximum value is "101". In the third test case, the string s with the maximum value is "111". In the fourth test case, the only string s of length 4, which has exactly 0 symbols, equal to "1" is "0000" and the value of f for that string is 0, so the answer is 0. In the fifth test case, the string s with the maximum value is "01010" and it is described as an example in the problem statement. Submitted Solution: ``` def solve_c(): n = int(input()) for _ in range(n): c() def c(): n, m = [int(x) for x in input().split()] if m == 0: print(0) return if m == 1: print(2*n-2) else: print(n*(n+1)//2+m-n) solve_c() ``` No
104,568
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Ayoub thinks that he is a very smart person, so he created a function f(s), where s is a binary string (a string which contains only symbols "0" and "1"). The function f(s) is equal to the number of substrings in the string s that contains at least one symbol, that is equal to "1". More formally, f(s) is equal to the number of pairs of integers (l, r), such that 1 ≤ l ≤ r ≤ |s| (where |s| is equal to the length of string s), such that at least one of the symbols s_l, s_{l+1}, …, s_r is equal to "1". For example, if s = "01010" then f(s) = 12, because there are 12 such pairs (l, r): (1, 2), (1, 3), (1, 4), (1, 5), (2, 2), (2, 3), (2, 4), (2, 5), (3, 4), (3, 5), (4, 4), (4, 5). Ayoub also thinks that he is smarter than Mahmoud so he gave him two integers n and m and asked him this problem. For all binary strings s of length n which contains exactly m symbols equal to "1", find the maximum value of f(s). Mahmoud couldn't solve the problem so he asked you for help. Can you help him? Input The input consists of multiple test cases. The first line contains a single integer t (1 ≤ t ≤ 10^5) — the number of test cases. The description of the test cases follows. The only line for each test case contains two integers n, m (1 ≤ n ≤ 10^{9}, 0 ≤ m ≤ n) — the length of the string and the number of symbols equal to "1" in it. Output For every test case print one integer number — the maximum value of f(s) over all strings s of length n, which has exactly m symbols, equal to "1". Example Input 5 3 1 3 2 3 3 4 0 5 2 Output 4 5 6 0 12 Note In the first test case, there exists only 3 strings of length 3, which has exactly 1 symbol, equal to "1". These strings are: s_1 = "100", s_2 = "010", s_3 = "001". The values of f for them are: f(s_1) = 3, f(s_2) = 4, f(s_3) = 3, so the maximum value is 4 and the answer is 4. In the second test case, the string s with the maximum value is "101". In the third test case, the string s with the maximum value is "111". In the fourth test case, the only string s of length 4, which has exactly 0 symbols, equal to "1" is "0000" and the value of f for that string is 0, so the answer is 0. In the fifth test case, the string s with the maximum value is "01010" and it is described as an example in the problem statement. Submitted Solution: ``` # -*- coding: utf-8 -*- import bisect import heapq import math import random import sys from collections import Counter, defaultdict, deque from decimal import ROUND_CEILING, ROUND_HALF_UP, Decimal from functools import lru_cache, reduce from itertools import combinations, combinations_with_replacement, product, permutations from operator import add, mul, sub sys.setrecursionlimit(100000) input = sys.stdin.readline # -*- coding: utf-8 -*- sys.setrecursionlimit(100000) input = sys.stdin.readline INF = 2**62-1 def read_int(): return int(input()) def read_int_n(): return list(map(int, input().split())) def read_float(): return float(input()) def read_float_n(): return list(map(float, input().split())) def read_str(): return input().strip() def read_str_n(): return list(map(str, input().split())) def error_print(*args): print(*args, file=sys.stderr) def mt(f): import time def wrap(*args, **kwargs): s = time.time() ret = f(*args, **kwargs) e = time.time() error_print(e - s, 'sec') return ret return wrap def slv(N, M): if M == 0: return 0 if M == N: return ((N+1) * N ) // 2 ans = ((N+1) * N) // 2 r = N - M d = r // (M+1) e = r % (M+1) if d != 0: ans -= (((d+1) * d) // 2) * (M+1 - e) ans -= (((d-1) * d) // 2) * (e) else: ans -= r return ans def main(): T = read_int() for _ in range(T): N, M = read_int_n() print(slv(N, M)) if __name__ == "__main__": main() ``` No
104,569
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Ayoub thinks that he is a very smart person, so he created a function f(s), where s is a binary string (a string which contains only symbols "0" and "1"). The function f(s) is equal to the number of substrings in the string s that contains at least one symbol, that is equal to "1". More formally, f(s) is equal to the number of pairs of integers (l, r), such that 1 ≤ l ≤ r ≤ |s| (where |s| is equal to the length of string s), such that at least one of the symbols s_l, s_{l+1}, …, s_r is equal to "1". For example, if s = "01010" then f(s) = 12, because there are 12 such pairs (l, r): (1, 2), (1, 3), (1, 4), (1, 5), (2, 2), (2, 3), (2, 4), (2, 5), (3, 4), (3, 5), (4, 4), (4, 5). Ayoub also thinks that he is smarter than Mahmoud so he gave him two integers n and m and asked him this problem. For all binary strings s of length n which contains exactly m symbols equal to "1", find the maximum value of f(s). Mahmoud couldn't solve the problem so he asked you for help. Can you help him? Input The input consists of multiple test cases. The first line contains a single integer t (1 ≤ t ≤ 10^5) — the number of test cases. The description of the test cases follows. The only line for each test case contains two integers n, m (1 ≤ n ≤ 10^{9}, 0 ≤ m ≤ n) — the length of the string and the number of symbols equal to "1" in it. Output For every test case print one integer number — the maximum value of f(s) over all strings s of length n, which has exactly m symbols, equal to "1". Example Input 5 3 1 3 2 3 3 4 0 5 2 Output 4 5 6 0 12 Note In the first test case, there exists only 3 strings of length 3, which has exactly 1 symbol, equal to "1". These strings are: s_1 = "100", s_2 = "010", s_3 = "001". The values of f for them are: f(s_1) = 3, f(s_2) = 4, f(s_3) = 3, so the maximum value is 4 and the answer is 4. In the second test case, the string s with the maximum value is "101". In the third test case, the string s with the maximum value is "111". In the fourth test case, the only string s of length 4, which has exactly 0 symbols, equal to "1" is "0000" and the value of f for that string is 0, so the answer is 0. In the fifth test case, the string s with the maximum value is "01010" and it is described as an example in the problem statement. Submitted Solution: ``` """ Author : thekushalghosh Team : CodeDiggers """ import sys,math input = sys.stdin.readline ############ ---- USER DEFINED INPUT FUNCTIONS ---- ############ def inp(): return(int(input())) def inlt(): return(list(map(int,input().split()))) def insr(): s = input() return(s[:len(s) - 1]) def invr(): return(map(int,input().split())) ################################################################ ############ ---- THE ACTUAL CODE STARTS BELOW ---- ############ t = 1 t = inp() def qw(n): return(n * (n + 1) // 2) for tt in range(t): n,m = invr() q = n - m if m == 0: print(0) continue ww = (n * (n + 1) // 2) w = q % ww qq = q // ww ww = ww - (w * qw(qq + 1)) - ((m + 1 - w) * qw(qq)) print(ww) ``` No
104,570
Provide tags and a correct Python 3 solution for this coding contest problem. You are given a tree consisting of n nodes. You want to write some labels on the tree's edges such that the following conditions hold: * Every label is an integer between 0 and n-2 inclusive. * All the written labels are distinct. * The largest value among MEX(u,v) over all pairs of nodes (u,v) is as small as possible. Here, MEX(u,v) denotes the smallest non-negative integer that isn't written on any edge on the unique simple path from node u to node v. Input The first line contains the integer n (2 ≤ n ≤ 10^5) — the number of nodes in the tree. Each of the next n-1 lines contains two space-separated integers u and v (1 ≤ u,v ≤ n) that mean there's an edge between nodes u and v. It's guaranteed that the given graph is a tree. Output Output n-1 integers. The i^{th} of them will be the number written on the i^{th} edge (in the input order). Examples Input 3 1 2 1 3 Output 0 1 Input 6 1 2 1 3 2 4 2 5 5 6 Output 0 3 2 4 1 Note The tree from the second sample: <image> Tags: constructive algorithms, dfs and similar, greedy, trees Correct Solution: ``` from sys import stdin try: n=int(stdin.readline().rstrip()) l=[0]*(n+1) arr=[] for _ in range(n-1): u,v=map(int,stdin.readline().rstrip().split()) arr.append((u,v)) l[u]+=1 l[v]+=1 x,y=0,n-2 for u,v in arr: if l[u]==1 or l[v]==1: print(x) x+=1 else: print(y) y-=1 except: pass ```
104,571
Provide tags and a correct Python 3 solution for this coding contest problem. You are given a tree consisting of n nodes. You want to write some labels on the tree's edges such that the following conditions hold: * Every label is an integer between 0 and n-2 inclusive. * All the written labels are distinct. * The largest value among MEX(u,v) over all pairs of nodes (u,v) is as small as possible. Here, MEX(u,v) denotes the smallest non-negative integer that isn't written on any edge on the unique simple path from node u to node v. Input The first line contains the integer n (2 ≤ n ≤ 10^5) — the number of nodes in the tree. Each of the next n-1 lines contains two space-separated integers u and v (1 ≤ u,v ≤ n) that mean there's an edge between nodes u and v. It's guaranteed that the given graph is a tree. Output Output n-1 integers. The i^{th} of them will be the number written on the i^{th} edge (in the input order). Examples Input 3 1 2 1 3 Output 0 1 Input 6 1 2 1 3 2 4 2 5 5 6 Output 0 3 2 4 1 Note The tree from the second sample: <image> Tags: constructive algorithms, dfs and similar, greedy, trees Correct Solution: ``` def solve(graph): ans = [-1 for i in range(len(graph) - 1)] for v in graph: if len(graph[v]) > 2: for i, (u, k) in enumerate(graph[v][:3]): ans[k] = i k = 0 for i in range(3, len(ans)): while ans[k] != -1: k += 1 ans[k] = i return ans return list(range(len(graph) - 1)) def test(): g1 = {1: [(2, 0), (3, 1)], 2: [(1, 0)], 3: [(1, 1)]} s1 = solve(g1) print(s1) assert s1 == [0, 1] g2 = {1: [(2, 0), (3, 1)], 2: [(1, 0), (4, 2), (5, 3)], 3: [(1, 1)], 4: [(2, 2)], 5: [(2, 3), (6, 5)], 6: [(5, 5)]} s2 = solve(g2) print(s2) assert s2 == [0, 3, 1, 2, 4] if __name__ == '__main__': # test() n = int(input()) graph = {i : [] for i in range(1, n + 1)} edges = [] for i in range(n - 1): u, v = [int(c) for c in input().split()] graph[u].append((v, i)) graph[v].append((u, i)) ans = solve(graph) print(*ans, sep='\n') ```
104,572
Provide tags and a correct Python 3 solution for this coding contest problem. You are given a tree consisting of n nodes. You want to write some labels on the tree's edges such that the following conditions hold: * Every label is an integer between 0 and n-2 inclusive. * All the written labels are distinct. * The largest value among MEX(u,v) over all pairs of nodes (u,v) is as small as possible. Here, MEX(u,v) denotes the smallest non-negative integer that isn't written on any edge on the unique simple path from node u to node v. Input The first line contains the integer n (2 ≤ n ≤ 10^5) — the number of nodes in the tree. Each of the next n-1 lines contains two space-separated integers u and v (1 ≤ u,v ≤ n) that mean there's an edge between nodes u and v. It's guaranteed that the given graph is a tree. Output Output n-1 integers. The i^{th} of them will be the number written on the i^{th} edge (in the input order). Examples Input 3 1 2 1 3 Output 0 1 Input 6 1 2 1 3 2 4 2 5 5 6 Output 0 3 2 4 1 Note The tree from the second sample: <image> Tags: constructive algorithms, dfs and similar, greedy, trees Correct Solution: ``` #!/usr/bin/env python # coding: utf-8 # In[83]: n = int(input()) edges = [] degrees = [0] for i in range(n): degrees.append(0) # In[84]: output = [] for i in range(n-1): output.append(-1) # In[85]: def d3(): d3_vertex = 0 for i in range(n+1): if ( degrees[i] > 2 ): d3_vertex = i return d3_vertex # In[86]: for i in range (n-1): inp = input().split() inp = [int(i) for i in inp] inp.sort() edges.append(inp) degrees[inp[0]]= degrees[inp[0]] +1 degrees[inp[1]]= degrees[inp[1]] +1 # In[91]: f = d3() if (f > 0): u = 0; for i in range(n-1): if(edges[i][0]==f or edges[i][1]==f): output[i] = u u = u+1 for i in range(n-1): if(output[i]==-1): output[i] = u u = u+1 for i in range(n-1): print(output[i]) else: for i in range(n-1): print(i) # In[ ]: ```
104,573
Provide tags and a correct Python 3 solution for this coding contest problem. You are given a tree consisting of n nodes. You want to write some labels on the tree's edges such that the following conditions hold: * Every label is an integer between 0 and n-2 inclusive. * All the written labels are distinct. * The largest value among MEX(u,v) over all pairs of nodes (u,v) is as small as possible. Here, MEX(u,v) denotes the smallest non-negative integer that isn't written on any edge on the unique simple path from node u to node v. Input The first line contains the integer n (2 ≤ n ≤ 10^5) — the number of nodes in the tree. Each of the next n-1 lines contains two space-separated integers u and v (1 ≤ u,v ≤ n) that mean there's an edge between nodes u and v. It's guaranteed that the given graph is a tree. Output Output n-1 integers. The i^{th} of them will be the number written on the i^{th} edge (in the input order). Examples Input 3 1 2 1 3 Output 0 1 Input 6 1 2 1 3 2 4 2 5 5 6 Output 0 3 2 4 1 Note The tree from the second sample: <image> Tags: constructive algorithms, dfs and similar, greedy, trees Correct Solution: ``` """ Template written to be used by Python Programmers. Use at your own risk!!!! Owned by enraged(rating - 5 star at CodeChef and Specialist at Codeforces). """ import sys import heapq from math import ceil, floor, gcd, fabs, factorial, fmod, sqrt from collections import defaultdict as dd, deque, Counter as c from itertools import combinations as comb, permutations as perm from bisect import bisect_left as bl, bisect_right as br, bisect # sys.setrecursionlimit(2*pow(10, 6)) # sys.stdin = open("input.txt", "r") # sys.stdout = open("output.txt", "w") mod = pow(10, 9) + 7 mod2 = 998244353 def data(): return sys.stdin.readline().strip() def out(var): sys.stdout.write(str(var)) def l(): return list(sp()) def sl(): return list(ssp()) def sp(): return map(int, data().split()) def ssp(): return map(str, data().split()) def l1d(n, val=0): return [val for i in range(n)] def l2d(n, m, val=0): return [[val for i in range(n)] for j in range(m)] def maxDeg(): for i in graph.keys(): if len(graph[i]) >= 3: return i return 0 n = int(data()) graph = dd(set) mat = [] for i in range(n-1): a, b = sp() mat.append((a, b)) graph[a].add(b) graph[b].add(a) m = maxDeg() dist, length, j = len(graph[m])-1, len(graph[m])-1, 1 for i in mat: if i[0] == m and dist >= 0: out(str(length-dist)+"\n") dist -= 1 elif i[1] == m and dist >= 0: out(str(length-dist)+"\n") dist -= 1 else: out(str(length+j)+"\n") j += 1 ```
104,574
Provide tags and a correct Python 3 solution for this coding contest problem. You are given a tree consisting of n nodes. You want to write some labels on the tree's edges such that the following conditions hold: * Every label is an integer between 0 and n-2 inclusive. * All the written labels are distinct. * The largest value among MEX(u,v) over all pairs of nodes (u,v) is as small as possible. Here, MEX(u,v) denotes the smallest non-negative integer that isn't written on any edge on the unique simple path from node u to node v. Input The first line contains the integer n (2 ≤ n ≤ 10^5) — the number of nodes in the tree. Each of the next n-1 lines contains two space-separated integers u and v (1 ≤ u,v ≤ n) that mean there's an edge between nodes u and v. It's guaranteed that the given graph is a tree. Output Output n-1 integers. The i^{th} of them will be the number written on the i^{th} edge (in the input order). Examples Input 3 1 2 1 3 Output 0 1 Input 6 1 2 1 3 2 4 2 5 5 6 Output 0 3 2 4 1 Note The tree from the second sample: <image> Tags: constructive algorithms, dfs and similar, greedy, trees Correct Solution: ``` #!/usr/bin/env python from __future__ import division, print_function import os import sys from io import BytesIO, IOBase import collections if sys.version_info[0] < 3: from __builtin__ import xrange as range from future_builtins import ascii, filter, hex, map, oct, zip def solution(): n = int(input().strip()) d = collections.defaultdict(int) e = [] for _ in range(n-1): i, j = [int(x) for x in input().strip().split(" ")] e.append((i, j)) d[i] += 1 d[j] += 1 need = min(3, list(d.values()).count(1)) if need == 2: for i in range(n-1): print(i) else: cur = 3 for x in e: if d[x[0]] == 1 or d[x[1]] == 1: if need == 3: print(0) need -= 1 elif need == 2: print(1) need -= 1 elif need == 1: print(2) need -= 1 else: print(cur) cur += 1 else: print(cur) cur += 1 def main(): # T = int(input().strip()) for _ in range(1): solution() # region fastio BUFSIZE = 8192 class FastIO(IOBase): newlines = 0 def __init__(self, file): self._fd = file.fileno() self.buffer = BytesIO() self.writable = "x" in file.mode or "r" not in file.mode self.write = self.buffer.write if self.writable else None def read(self): while True: b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE)) if not b: break ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines = 0 return self.buffer.read() def readline(self): while self.newlines == 0: b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE)) self.newlines = b.count(b"\n") + (not b) ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines -= 1 return self.buffer.readline() def flush(self): if self.writable: os.write(self._fd, self.buffer.getvalue()) self.buffer.truncate(0), self.buffer.seek(0) class IOWrapper(IOBase): def __init__(self, file): self.buffer = FastIO(file) self.flush = self.buffer.flush self.writable = self.buffer.writable self.write = lambda s: self.buffer.write(s.encode("ascii")) self.read = lambda: self.buffer.read().decode("ascii") self.readline = lambda: self.buffer.readline().decode("ascii") def print(*args, **kwargs): """Prints the values to a stream, or to sys.stdout by default.""" sep, file = kwargs.pop("sep", " "), kwargs.pop("file", sys.stdout) at_start = True for x in args: if not at_start: file.write(sep) file.write(str(x)) at_start = False file.write(kwargs.pop("end", "\n")) if kwargs.pop("flush", False): file.flush() if sys.version_info[0] < 3: sys.stdin, sys.stdout = FastIO(sys.stdin), FastIO(sys.stdout) else: sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout) input = lambda: sys.stdin.readline().rstrip("\r\n") # endregion if __name__ == "__main__": main() ```
104,575
Provide tags and a correct Python 3 solution for this coding contest problem. You are given a tree consisting of n nodes. You want to write some labels on the tree's edges such that the following conditions hold: * Every label is an integer between 0 and n-2 inclusive. * All the written labels are distinct. * The largest value among MEX(u,v) over all pairs of nodes (u,v) is as small as possible. Here, MEX(u,v) denotes the smallest non-negative integer that isn't written on any edge on the unique simple path from node u to node v. Input The first line contains the integer n (2 ≤ n ≤ 10^5) — the number of nodes in the tree. Each of the next n-1 lines contains two space-separated integers u and v (1 ≤ u,v ≤ n) that mean there's an edge between nodes u and v. It's guaranteed that the given graph is a tree. Output Output n-1 integers. The i^{th} of them will be the number written on the i^{th} edge (in the input order). Examples Input 3 1 2 1 3 Output 0 1 Input 6 1 2 1 3 2 4 2 5 5 6 Output 0 3 2 4 1 Note The tree from the second sample: <image> Tags: constructive algorithms, dfs and similar, greedy, trees Correct Solution: ``` n = int(input()) deg = [0]*(n+2) es = [] for i in range(n-1): a,b = list(map(int, input().split())) deg[a]+=1 deg[b]+=1 es.append((a,b)) if max(deg)==2: for i in range(n-1): print(i) else: k = deg.index(max(deg)) e_012 = 0 cnt = 3 for e in es: if k in e and e_012 < 3: print(e_012) e_012+=1 else: print(cnt) cnt+=1 ```
104,576
Provide tags and a correct Python 3 solution for this coding contest problem. You are given a tree consisting of n nodes. You want to write some labels on the tree's edges such that the following conditions hold: * Every label is an integer between 0 and n-2 inclusive. * All the written labels are distinct. * The largest value among MEX(u,v) over all pairs of nodes (u,v) is as small as possible. Here, MEX(u,v) denotes the smallest non-negative integer that isn't written on any edge on the unique simple path from node u to node v. Input The first line contains the integer n (2 ≤ n ≤ 10^5) — the number of nodes in the tree. Each of the next n-1 lines contains two space-separated integers u and v (1 ≤ u,v ≤ n) that mean there's an edge between nodes u and v. It's guaranteed that the given graph is a tree. Output Output n-1 integers. The i^{th} of them will be the number written on the i^{th} edge (in the input order). Examples Input 3 1 2 1 3 Output 0 1 Input 6 1 2 1 3 2 4 2 5 5 6 Output 0 3 2 4 1 Note The tree from the second sample: <image> Tags: constructive algorithms, dfs and similar, greedy, trees Correct Solution: ``` # ------------------- fast io -------------------- import os import sys from io import BytesIO, IOBase BUFSIZE = 8192 class FastIO(IOBase): newlines = 0 def __init__(self, file): self._fd = file.fileno() self.buffer = BytesIO() self.writable = "x" in file.mode or "r" not in file.mode self.write = self.buffer.write if self.writable else None def read(self): while True: b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE)) if not b: break ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines = 0 return self.buffer.read() def readline(self): while self.newlines == 0: b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE)) self.newlines = b.count(b"\n") + (not b) ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines -= 1 return self.buffer.readline() def flush(self): if self.writable: os.write(self._fd, self.buffer.getvalue()) self.buffer.truncate(0), self.buffer.seek(0) class IOWrapper(IOBase): def __init__(self, file): self.buffer = FastIO(file) self.flush = self.buffer.flush self.writable = self.buffer.writable self.write = lambda s: self.buffer.write(s.encode("ascii")) self.read = lambda: self.buffer.read().decode("ascii") self.readline = lambda: self.buffer.readline().decode("ascii") sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout) input = lambda: sys.stdin.readline().rstrip("\r\n") # ------------------- fast io -------------------- n=int(input()) graph=[[] for s in range(n)] inds={} leaf=set([]) for s in range(n-1): u,v=map(int,input().split()) u-=1 v-=1 inds[(u,v)]=s inds[(v,u)]=s graph[u].append(v) graph[v].append(u) if len(graph[u])==1: leaf.add(u) else: if u in leaf: leaf.remove(u) if len(graph[v])==1: leaf.add(v) else: if v in leaf: leaf.remove(v) ans=[-1 for s in range(n-1)] cv=0 if len(leaf)>=3: while len(leaf)>0: v0=leaf.pop() v1=graph[v0][0] ind=inds[(v0,v1)] ans[ind]=cv cv+=1 for s in range(n-1): if ans[s-1]==-1: ans[s-1]=cv cv+=1 else: #then u can really do much for s in range(n-1): ans[s]=s for s in range(n-1): print(ans[s]) ```
104,577
Provide tags and a correct Python 3 solution for this coding contest problem. You are given a tree consisting of n nodes. You want to write some labels on the tree's edges such that the following conditions hold: * Every label is an integer between 0 and n-2 inclusive. * All the written labels are distinct. * The largest value among MEX(u,v) over all pairs of nodes (u,v) is as small as possible. Here, MEX(u,v) denotes the smallest non-negative integer that isn't written on any edge on the unique simple path from node u to node v. Input The first line contains the integer n (2 ≤ n ≤ 10^5) — the number of nodes in the tree. Each of the next n-1 lines contains two space-separated integers u and v (1 ≤ u,v ≤ n) that mean there's an edge between nodes u and v. It's guaranteed that the given graph is a tree. Output Output n-1 integers. The i^{th} of them will be the number written on the i^{th} edge (in the input order). Examples Input 3 1 2 1 3 Output 0 1 Input 6 1 2 1 3 2 4 2 5 5 6 Output 0 3 2 4 1 Note The tree from the second sample: <image> Tags: constructive algorithms, dfs and similar, greedy, trees Correct Solution: ``` def solve(n, queries): node = 0 count = [0] * (n + 1) for u, v in queries: count[u] += 1 count[v] += 1 if count[u] == 3: node = u if count[v] == 3: node = v j = 0 ans = [-1] * len(queries) for i, pair in enumerate(queries): if node in pair: ans[i] = j j += 1 for i in range(len(queries)): if ans[i] != -1: continue ans[i] = j j += 1 for i in ans: print(i) def smain(): inp = lambda: [int(x) for x in input().split()] n = int(input()) queries = [inp() for _ in range(n - 1)] solve(n, queries) if __name__ == '__main__': smain() ```
104,578
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given a tree consisting of n nodes. You want to write some labels on the tree's edges such that the following conditions hold: * Every label is an integer between 0 and n-2 inclusive. * All the written labels are distinct. * The largest value among MEX(u,v) over all pairs of nodes (u,v) is as small as possible. Here, MEX(u,v) denotes the smallest non-negative integer that isn't written on any edge on the unique simple path from node u to node v. Input The first line contains the integer n (2 ≤ n ≤ 10^5) — the number of nodes in the tree. Each of the next n-1 lines contains two space-separated integers u and v (1 ≤ u,v ≤ n) that mean there's an edge between nodes u and v. It's guaranteed that the given graph is a tree. Output Output n-1 integers. The i^{th} of them will be the number written on the i^{th} edge (in the input order). Examples Input 3 1 2 1 3 Output 0 1 Input 6 1 2 1 3 2 4 2 5 5 6 Output 0 3 2 4 1 Note The tree from the second sample: <image> Submitted Solution: ``` MOD = 1000000007 MOD2 = 998244353 ii = lambda: int(input()) si = lambda: input() dgl = lambda: list(map(int, input())) f = lambda: map(int, input().split()) il = lambda: list(map(int, input().split())) ls = lambda: list(input()) let = '@abcdefghijklmnopqrstuvwxyz' n=ii() deg=[0]*(10**5+10) l=[] it1,it2=0,n-2 for _ in range(n-1): x,y=f() deg[x]+=1 deg[y]+=1 l.append([x,y]) for i in l: if deg[i[0]]==1 or deg[i[1]]==1: print(it1) it1+=1 else: print(it2) it2-=1 ``` Yes
104,579
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given a tree consisting of n nodes. You want to write some labels on the tree's edges such that the following conditions hold: * Every label is an integer between 0 and n-2 inclusive. * All the written labels are distinct. * The largest value among MEX(u,v) over all pairs of nodes (u,v) is as small as possible. Here, MEX(u,v) denotes the smallest non-negative integer that isn't written on any edge on the unique simple path from node u to node v. Input The first line contains the integer n (2 ≤ n ≤ 10^5) — the number of nodes in the tree. Each of the next n-1 lines contains two space-separated integers u and v (1 ≤ u,v ≤ n) that mean there's an edge between nodes u and v. It's guaranteed that the given graph is a tree. Output Output n-1 integers. The i^{th} of them will be the number written on the i^{th} edge (in the input order). Examples Input 3 1 2 1 3 Output 0 1 Input 6 1 2 1 3 2 4 2 5 5 6 Output 0 3 2 4 1 Note The tree from the second sample: <image> Submitted Solution: ``` n = int(input()) degree = [0] * (n + 1) order = [] for _ in range(n-1): x, y = map(int, input().split()) degree[x] += 1 degree[y] += 1 order.append((x, y)) res1 = 0; res2 = n-2 k = 0 for d in range(n+1): if degree[d] >= 3: k = d break for x, y in order: if x == k or y == k: print(res1) res1 += 1 else: print(res2) res2 -= 1 ``` Yes
104,580
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given a tree consisting of n nodes. You want to write some labels on the tree's edges such that the following conditions hold: * Every label is an integer between 0 and n-2 inclusive. * All the written labels are distinct. * The largest value among MEX(u,v) over all pairs of nodes (u,v) is as small as possible. Here, MEX(u,v) denotes the smallest non-negative integer that isn't written on any edge on the unique simple path from node u to node v. Input The first line contains the integer n (2 ≤ n ≤ 10^5) — the number of nodes in the tree. Each of the next n-1 lines contains two space-separated integers u and v (1 ≤ u,v ≤ n) that mean there's an edge between nodes u and v. It's guaranteed that the given graph is a tree. Output Output n-1 integers. The i^{th} of them will be the number written on the i^{th} edge (in the input order). Examples Input 3 1 2 1 3 Output 0 1 Input 6 1 2 1 3 2 4 2 5 5 6 Output 0 3 2 4 1 Note The tree from the second sample: <image> Submitted Solution: ``` ''' Ehab and Path-etic MEXs - spoiled by mzy ''' ''' routine ''' N = int(input()) leaves = {} edges = [0 for i in range(N)] for edge in range(N - 1): a, b = list(map(int, input().split())) for node in (a, b): edges[node - 1] += 1 if edges[node - 1] == 1: leaves[node] = edge elif edges[node - 1] == 2: del leaves[node] if len(leaves) < 3: for n in range(N - 1): print(n) else: start = 3 leaf = 0 specials = list(leaves.values())[:3] for edge in range(N - 1): if edge in specials: print(leaf) leaf += 1 else: print(start) start += 1 # print(specials) ``` Yes
104,581
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given a tree consisting of n nodes. You want to write some labels on the tree's edges such that the following conditions hold: * Every label is an integer between 0 and n-2 inclusive. * All the written labels are distinct. * The largest value among MEX(u,v) over all pairs of nodes (u,v) is as small as possible. Here, MEX(u,v) denotes the smallest non-negative integer that isn't written on any edge on the unique simple path from node u to node v. Input The first line contains the integer n (2 ≤ n ≤ 10^5) — the number of nodes in the tree. Each of the next n-1 lines contains two space-separated integers u and v (1 ≤ u,v ≤ n) that mean there's an edge between nodes u and v. It's guaranteed that the given graph is a tree. Output Output n-1 integers. The i^{th} of them will be the number written on the i^{th} edge (in the input order). Examples Input 3 1 2 1 3 Output 0 1 Input 6 1 2 1 3 2 4 2 5 5 6 Output 0 3 2 4 1 Note The tree from the second sample: <image> Submitted Solution: ``` import math,sys,bisect,heapq from collections import defaultdict,Counter,deque from itertools import groupby,accumulate from functools import lru_cache #sys.setrecursionlimit(200000000) int1 = lambda x: int(x) - 1 #def input(): return sys.stdin.readline().strip()m input = iter(sys.stdin.buffer.read().decode().splitlines()).__next__ aj = lambda: list(map(int, input().split())) def list3d(a, b, c, d): return [[[d] * c for j in range(b)] for i in range(a)] #MOD = 1000000000 + 7 def Y(c): print(["NO","YES"][c]) def y(c): print(["no","yes"][c]) def Yy(c): print(["No","Yes"][c]) G = defaultdict(list) C = Counter() order = [] def addEdge(a,b): G[a].append(b) G[b].append(a) C[a] += 1 C[b] += 1 order.append((a,b)) n, = aj() for i in range(n-1): a,b = aj() addEdge(a,b) # print(C) # print(G) E = [] for i in C.keys(): E.append((C[i],i)) E.sort() mark = {} p = 0 for i,j in E: for l in G[j]: if mark.get((j,l),-1) == -1: mark[(j,l)] = p mark[(l,j)] = p p+=1 for i in order: print(mark[i]) ``` Yes
104,582
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given a tree consisting of n nodes. You want to write some labels on the tree's edges such that the following conditions hold: * Every label is an integer between 0 and n-2 inclusive. * All the written labels are distinct. * The largest value among MEX(u,v) over all pairs of nodes (u,v) is as small as possible. Here, MEX(u,v) denotes the smallest non-negative integer that isn't written on any edge on the unique simple path from node u to node v. Input The first line contains the integer n (2 ≤ n ≤ 10^5) — the number of nodes in the tree. Each of the next n-1 lines contains two space-separated integers u and v (1 ≤ u,v ≤ n) that mean there's an edge between nodes u and v. It's guaranteed that the given graph is a tree. Output Output n-1 integers. The i^{th} of them will be the number written on the i^{th} edge (in the input order). Examples Input 3 1 2 1 3 Output 0 1 Input 6 1 2 1 3 2 4 2 5 5 6 Output 0 3 2 4 1 Note The tree from the second sample: <image> Submitted Solution: ``` import math import fractions def make_divisors(n): divisors = [] for i in range(1, int(n**0.5)+1): if n % i == 0: divisors.append(i) if i != n // i: divisors.append(n//i) # divisors.sort() return divisors def ValueToBits(x,digit): res = [0 for i in range(digit)] now = x for i in range(digit): res[i]=now%2 now = now >> 1 return res def BitsToValue(arr): n = len(arr) ans = 0 for i in range(n): ans+= arr[i] * 2**i return ans def ValueToArray10(x, digit): ans = [0 for i in range(digit)] now = x for i in range(digit): ans[digit-i-1] = now%10 now = now //10 return ans ''' def cmb(n, r, p): if (r < 0) or (n < r): return 0 r = min(r, n - r) return fact[n] * factinv[r] * factinv[n-r] % p p = 10 ** 9 + 7 N = 10 ** 6 + 2 fact = [1, 1] # fact[n] = (n! mod p) factinv = [1, 1] # factinv[n] = ((n!)^(-1) mod p) inv = [0, 1] # factinv 計算用 for i in range(2, N + 1): fact.append((fact[-1] * i) % p) inv.append((-inv[p % i] * (p // i)) % p) factinv.append((factinv[-1] * inv[-1]) % p) ''' #a = list(map(int, input().split())) n = int(input()) nb = [[] for i in range(n)] nbe = [[] for i in range(n)] es = [] for i in range(n-1): a,b = list(map(int, input().split())) a -= 1 b -= 1 es.append([a,b]) nb[a].append(b) nb[b].append(a) nbe[a].append(i) nbe[b].append(i) start=-1 for i in range(n): if(len(nb[i])==1): start=i break queue=[start] done=0 checked=[0 for i in range(n)] checked[start] = 1 u = -1 v = -1 w = -1 while(True): #print(queue,done) if(len(queue)==done): #print("b") break else: now = queue[done] nownb = nb[now] #print("a",now,nownb,done) if(len(nownb)<=2): for j in range(len(nownb)): if(checked[nownb[j]]==0): queue.append(nownb[j]) checked[nownb[j]]=1 done+=1 else: u = nbe[now][0] v = nbe[now][1] w = nbe[now][2] break #print(u,v,w) print(checked) ans = [0 for i in range(n-1)] now = 3 if(u!=-1): for i in range(n-1): if(i==u): print(0) elif(i==v): print(1) elif(i==w): print(2) else: print(now) now+=1 else: for i in range(n-1): print(i) ``` No
104,583
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given a tree consisting of n nodes. You want to write some labels on the tree's edges such that the following conditions hold: * Every label is an integer between 0 and n-2 inclusive. * All the written labels are distinct. * The largest value among MEX(u,v) over all pairs of nodes (u,v) is as small as possible. Here, MEX(u,v) denotes the smallest non-negative integer that isn't written on any edge on the unique simple path from node u to node v. Input The first line contains the integer n (2 ≤ n ≤ 10^5) — the number of nodes in the tree. Each of the next n-1 lines contains two space-separated integers u and v (1 ≤ u,v ≤ n) that mean there's an edge between nodes u and v. It's guaranteed that the given graph is a tree. Output Output n-1 integers. The i^{th} of them will be the number written on the i^{th} edge (in the input order). Examples Input 3 1 2 1 3 Output 0 1 Input 6 1 2 1 3 2 4 2 5 5 6 Output 0 3 2 4 1 Note The tree from the second sample: <image> Submitted Solution: ``` from sys import stdin from collections import defaultdict input = stdin.readline def read_tuple(): return map(int,input().split()) def read_int(): return int(input()) def read_list(): return list(map(int,input().split())) def read_str_list(): return list(input().split()) n = read_int() tree = defaultdict(list) queries = [] for _ in range(n-1): u,v = read_tuple() tree[u].append(v) tree[v].append(u) if u>v: u,v = v,u queries.append( (u,v) ) ans = defaultdict(int) mex = 0 for u in range(1,n+1): if len(tree[u]) == 1: v = tree[u][0] if u>v: ans[ (v,u) ] = mex else: ans[ (u,v) ] = mex mex+=1 for u,v in queries: val = ans.get( (u,v), -1 ) if val==-1: print(mex) mex+=1 else: print(val) ``` No
104,584
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given a tree consisting of n nodes. You want to write some labels on the tree's edges such that the following conditions hold: * Every label is an integer between 0 and n-2 inclusive. * All the written labels are distinct. * The largest value among MEX(u,v) over all pairs of nodes (u,v) is as small as possible. Here, MEX(u,v) denotes the smallest non-negative integer that isn't written on any edge on the unique simple path from node u to node v. Input The first line contains the integer n (2 ≤ n ≤ 10^5) — the number of nodes in the tree. Each of the next n-1 lines contains two space-separated integers u and v (1 ≤ u,v ≤ n) that mean there's an edge between nodes u and v. It's guaranteed that the given graph is a tree. Output Output n-1 integers. The i^{th} of them will be the number written on the i^{th} edge (in the input order). Examples Input 3 1 2 1 3 Output 0 1 Input 6 1 2 1 3 2 4 2 5 5 6 Output 0 3 2 4 1 Note The tree from the second sample: <image> Submitted Solution: ``` n = int(input()) tree = [0] * (n+1) edges = [] for i in range(n-1): u, v = map(int, input().split()) edges.append((u, v)) tree[u] += 1 tree[v] += 1 left = 0 right = n-2 for u, v in edges: if tree[u] != 1 and tree[v] != 1: print(left) left += 1 else: print(right) right -= 1 ``` No
104,585
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given a tree consisting of n nodes. You want to write some labels on the tree's edges such that the following conditions hold: * Every label is an integer between 0 and n-2 inclusive. * All the written labels are distinct. * The largest value among MEX(u,v) over all pairs of nodes (u,v) is as small as possible. Here, MEX(u,v) denotes the smallest non-negative integer that isn't written on any edge on the unique simple path from node u to node v. Input The first line contains the integer n (2 ≤ n ≤ 10^5) — the number of nodes in the tree. Each of the next n-1 lines contains two space-separated integers u and v (1 ≤ u,v ≤ n) that mean there's an edge between nodes u and v. It's guaranteed that the given graph is a tree. Output Output n-1 integers. The i^{th} of them will be the number written on the i^{th} edge (in the input order). Examples Input 3 1 2 1 3 Output 0 1 Input 6 1 2 1 3 2 4 2 5 5 6 Output 0 3 2 4 1 Note The tree from the second sample: <image> Submitted Solution: ``` import sys n = int(input()) a = [] b = dict() num = False a = list(map(str.strip, sys.stdin)) for i in range(n - 1): if a[i][0] in b: b[a[i][0]] += 1 else: b[a[i][0]] = 1 if a[i][1] in b: b[a[i][1]] += 1 else: b[a[i][1]] = 1 if b[a[i][1]] == 3: num = a[i][1] break if b[a[i][0]] == 3: num = a[i][0] break count = 0 count2 = 3 if not num: for i in range(n - 1): print(count) count += 1 else: for i in range(n - 1): if (num in a[i]) and (count < 3): print(count) count += 1 else: print(count2) count2 += 1 ``` No
104,586
Provide tags and a correct Python 3 solution for this coding contest problem. A monopole magnet is a magnet that only has one pole, either north or south. They don't actually exist since real magnets have two poles, but this is a programming contest problem, so we don't care. There is an n× m grid. Initially, you may place some north magnets and some south magnets into the cells. You are allowed to place as many magnets as you like, even multiple in the same cell. An operation is performed as follows. Choose a north magnet and a south magnet to activate. If they are in the same row or the same column and they occupy different cells, then the north magnet moves one unit closer to the south magnet. Otherwise, if they occupy the same cell or do not share a row or column, then nothing changes. Note that the south magnets are immovable. Each cell of the grid is colored black or white. Let's consider ways to place magnets in the cells so that the following conditions are met. 1. There is at least one south magnet in every row and every column. 2. If a cell is colored black, then it is possible for a north magnet to occupy this cell after some sequence of operations from the initial placement. 3. If a cell is colored white, then it is impossible for a north magnet to occupy this cell after some sequence of operations from the initial placement. Determine if it is possible to place magnets such that these conditions are met. If it is possible, find the minimum number of north magnets required (there are no requirements on the number of south magnets). Input The first line contains two integers n and m (1≤ n,m≤ 1000) — the number of rows and the number of columns, respectively. The next n lines describe the coloring. The i-th of these lines contains a string of length m, where the j-th character denotes the color of the cell in row i and column j. The characters "#" and "." represent black and white, respectively. It is guaranteed, that the string will not contain any other characters. Output Output a single integer, the minimum possible number of north magnets required. If there is no placement of magnets that satisfies all conditions, print a single integer -1. Examples Input 3 3 .#. ### ##. Output 1 Input 4 2 ## .# .# ## Output -1 Input 4 5 ....# ####. .###. .#... Output 2 Input 2 1 . # Output -1 Input 3 5 ..... ..... ..... Output 0 Note In the first test, here is an example placement of magnets: <image> In the second test, we can show that no required placement of magnets exists. Here are three example placements that fail to meet the requirements. The first example violates rule 3 since we can move the north magnet down onto a white square. The second example violates rule 2 since we cannot move the north magnet to the bottom-left black square by any sequence of operations. The third example violates rule 1 since there is no south magnet in the first column. <image> In the third test, here is an example placement of magnets. We can show that there is no required placement of magnets with fewer north magnets. <image> In the fourth test, we can show that no required placement of magnets exists. Here are two example placements that fail to meet the requirements. The first example violates rule 1 since there is no south magnet in the first row. The second example violates rules 1 and 3 since there is no south magnet in the second row and we can move the north magnet up one unit onto a white square. <image> In the fifth test, we can put the south magnet in each cell and no north magnets. Because there are no black cells, it will be a correct placement. Tags: constructive algorithms, dfs and similar, dsu, graphs Correct Solution: ``` import sys from sys import stdin from collections import defaultdict import bisect import re def eprint(*args, **kwargs): print(*args, file=sys.stderr, **kwargs) def inputs(f=int): return list(map(f, stdin.readline().strip().split())) def fill_dfs_que(map_list, i, j, num): # dFS que = [(i, j)] while que: # fill center fill_i, fill_j = que.pop() map_list[fill_i][fill_j] = num # fill up if 0 <= fill_i-1 and map_list[fill_i - 1][fill_j] == '#': que.append((fill_i-1, fill_j)) # fill down if fill_i+1 < R and map_list[fill_i + 1][fill_j] == '#': que.append((fill_i+1, fill_j)) # fill left if 0 <= fill_j-1 and map_list[fill_i][fill_j - 1] == '#': que.append((fill_i, fill_j-1)) # fill right if fill_j+1 < C and map_list[fill_i][fill_j + 1] == '#': que.append((fill_i, fill_j+1)) def solve(map_all): # is possible? # 1. check empty row or col empty_row = [] for i, row in enumerate(map_all): if row == "." * C: empty_row.append(i) empty_col = [] for i in range(C): col = "".join([x[i] for x in map_all]) if col == '.' * R: empty_col.append(i) if len(empty_row) and len(empty_col)> 0: # 1-1 if n == max(empty row, empty col) : with place n south magnet pass elif empty_col or empty_row: return -1 # 2. check in-between black cell for i, row in enumerate(map_all): ret = re.search(r"#\.+#", row) if ret is not None: return -1 for i in range(C): col = "".join([x[i] for x in map_all]) ret = re.search(r"#\.+#", col) if ret is not None: return -1 map_list = [list(x) for x in map_all] # print(map_list) # make minimum! one island per each. island_num = "0" for i, row in enumerate(map_list): for j, char in enumerate(row): if map_list[i][j] == '#': island_num = str(int(island_num) + 1) fill_dfs_que(map_list, i, j, island_num) # print(island_num) # print(map_list) return int(island_num) if __name__ == '__main__': R, C = inputs() map_all = [] for i in range(R): map_row = input() map_all.append(map_row) ans = solve(map_all) print(ans) ```
104,587
Provide tags and a correct Python 3 solution for this coding contest problem. A monopole magnet is a magnet that only has one pole, either north or south. They don't actually exist since real magnets have two poles, but this is a programming contest problem, so we don't care. There is an n× m grid. Initially, you may place some north magnets and some south magnets into the cells. You are allowed to place as many magnets as you like, even multiple in the same cell. An operation is performed as follows. Choose a north magnet and a south magnet to activate. If they are in the same row or the same column and they occupy different cells, then the north magnet moves one unit closer to the south magnet. Otherwise, if they occupy the same cell or do not share a row or column, then nothing changes. Note that the south magnets are immovable. Each cell of the grid is colored black or white. Let's consider ways to place magnets in the cells so that the following conditions are met. 1. There is at least one south magnet in every row and every column. 2. If a cell is colored black, then it is possible for a north magnet to occupy this cell after some sequence of operations from the initial placement. 3. If a cell is colored white, then it is impossible for a north magnet to occupy this cell after some sequence of operations from the initial placement. Determine if it is possible to place magnets such that these conditions are met. If it is possible, find the minimum number of north magnets required (there are no requirements on the number of south magnets). Input The first line contains two integers n and m (1≤ n,m≤ 1000) — the number of rows and the number of columns, respectively. The next n lines describe the coloring. The i-th of these lines contains a string of length m, where the j-th character denotes the color of the cell in row i and column j. The characters "#" and "." represent black and white, respectively. It is guaranteed, that the string will not contain any other characters. Output Output a single integer, the minimum possible number of north magnets required. If there is no placement of magnets that satisfies all conditions, print a single integer -1. Examples Input 3 3 .#. ### ##. Output 1 Input 4 2 ## .# .# ## Output -1 Input 4 5 ....# ####. .###. .#... Output 2 Input 2 1 . # Output -1 Input 3 5 ..... ..... ..... Output 0 Note In the first test, here is an example placement of magnets: <image> In the second test, we can show that no required placement of magnets exists. Here are three example placements that fail to meet the requirements. The first example violates rule 3 since we can move the north magnet down onto a white square. The second example violates rule 2 since we cannot move the north magnet to the bottom-left black square by any sequence of operations. The third example violates rule 1 since there is no south magnet in the first column. <image> In the third test, here is an example placement of magnets. We can show that there is no required placement of magnets with fewer north magnets. <image> In the fourth test, we can show that no required placement of magnets exists. Here are two example placements that fail to meet the requirements. The first example violates rule 1 since there is no south magnet in the first row. The second example violates rules 1 and 3 since there is no south magnet in the second row and we can move the north magnet up one unit onto a white square. <image> In the fifth test, we can put the south magnet in each cell and no north magnets. Because there are no black cells, it will be a correct placement. Tags: constructive algorithms, dfs and similar, dsu, graphs Correct Solution: ``` import sys readline = sys.stdin.readline H, W = map(int, readline().split()) G = [[1 if s == '#' else 0 for s in readline().strip()] for _ in range(H)] DIREC = [(0, 1), (1, 0), (-1, 0), (0, -1)] def calc(): zh = 0 for i in range(H): cnt = 0 for j in range(W): if G[i][j]: if cnt == 0: cnt = 1 continue if cnt == 1: continue if cnt == 2: return -1 else: if cnt == 0: continue cnt = 2 if cnt == 0: zh = 1 zw = 0 for j in range(W): cnt = 0 for i in range(H): if G[i][j]: if cnt == 0: cnt = 1 continue if cnt == 1: continue if cnt == 2: return -1 else: if cnt == 0: continue cnt = 2 if cnt == 0: zw = 1 if zw^zh: return -1 ans = 0 used = set() geta = W for i in range(H): for j in range(W): if G[i][j] == 0: continue if (i*geta + j) in used: continue ans += 1 stack = [i*geta + j] while stack: nh, nw = divmod(stack.pop(), geta) for dh, dw in DIREC: fh, fw = nh+dh, nw+dw if not 0 <= fh < H or not 0 <= fw < W: continue if not G[fh][fw]: continue vf = fh*geta + fw if vf in used: continue stack.append(vf) used.add(vf) return ans print(calc()) ```
104,588
Provide tags and a correct Python 3 solution for this coding contest problem. A monopole magnet is a magnet that only has one pole, either north or south. They don't actually exist since real magnets have two poles, but this is a programming contest problem, so we don't care. There is an n× m grid. Initially, you may place some north magnets and some south magnets into the cells. You are allowed to place as many magnets as you like, even multiple in the same cell. An operation is performed as follows. Choose a north magnet and a south magnet to activate. If they are in the same row or the same column and they occupy different cells, then the north magnet moves one unit closer to the south magnet. Otherwise, if they occupy the same cell or do not share a row or column, then nothing changes. Note that the south magnets are immovable. Each cell of the grid is colored black or white. Let's consider ways to place magnets in the cells so that the following conditions are met. 1. There is at least one south magnet in every row and every column. 2. If a cell is colored black, then it is possible for a north magnet to occupy this cell after some sequence of operations from the initial placement. 3. If a cell is colored white, then it is impossible for a north magnet to occupy this cell after some sequence of operations from the initial placement. Determine if it is possible to place magnets such that these conditions are met. If it is possible, find the minimum number of north magnets required (there are no requirements on the number of south magnets). Input The first line contains two integers n and m (1≤ n,m≤ 1000) — the number of rows and the number of columns, respectively. The next n lines describe the coloring. The i-th of these lines contains a string of length m, where the j-th character denotes the color of the cell in row i and column j. The characters "#" and "." represent black and white, respectively. It is guaranteed, that the string will not contain any other characters. Output Output a single integer, the minimum possible number of north magnets required. If there is no placement of magnets that satisfies all conditions, print a single integer -1. Examples Input 3 3 .#. ### ##. Output 1 Input 4 2 ## .# .# ## Output -1 Input 4 5 ....# ####. .###. .#... Output 2 Input 2 1 . # Output -1 Input 3 5 ..... ..... ..... Output 0 Note In the first test, here is an example placement of magnets: <image> In the second test, we can show that no required placement of magnets exists. Here are three example placements that fail to meet the requirements. The first example violates rule 3 since we can move the north magnet down onto a white square. The second example violates rule 2 since we cannot move the north magnet to the bottom-left black square by any sequence of operations. The third example violates rule 1 since there is no south magnet in the first column. <image> In the third test, here is an example placement of magnets. We can show that there is no required placement of magnets with fewer north magnets. <image> In the fourth test, we can show that no required placement of magnets exists. Here are two example placements that fail to meet the requirements. The first example violates rule 1 since there is no south magnet in the first row. The second example violates rules 1 and 3 since there is no south magnet in the second row and we can move the north magnet up one unit onto a white square. <image> In the fifth test, we can put the south magnet in each cell and no north magnets. Because there are no black cells, it will be a correct placement. Tags: constructive algorithms, dfs and similar, dsu, graphs Correct Solution: ``` # Author: Uday Gupta def make_reachable(x, y): stack = [] stack.append((x, y)) while len(stack): s = stack[-1] stack.pop() i = s[0] j = s[1] if reachable_table[i][j] == 0: reachable_table[i][j] = 1 if i + 1 < n and grid[i + 1][j] == 'B': if reachable_table[i + 1][j] == 0: stack.append((i + 1,j)) if i - 1 >= 0 and grid[i - 1][j] == 'B': if reachable_table[i - 1][j] == 0: stack.append((i - 1, j)) if j + 1 < m and grid[i][j + 1] == 'B': if reachable_table[i][j + 1] == 0: stack.append((i,j + 1)) if j - 1 >= 0 and grid[i][j - 1] == 'B': if reachable_table[i][j - 1] == 0: stack.append((i,j - 1)) n, m = list(map(int, input().split())) grid = [] for i in range(n): l = input() u = [] for j in range(m): if l[j] == '#': u.append('B') else: u.append('W') grid.append(u) white_column = 0 white_row = 0 for i in range(n): row = grid[i] if 'B' in row: continue else: white_row = 1 for j in range(m): col = [] for i in range(n): col.append(grid[i][j]) if 'B' in col: continue else: white_column = 1 if (white_row == 1 and white_column == 0) or (white_row == 0 and white_column == 1): print(-1) exit() # if n == 1: # white_present = 0 # black_present = 0 # # for i in range(m): # if grid[0][i] == 'B': # black_present = 1 # if grid[0][i] == 'W': # white_present = 1 # if black_present == 1 and white_present == 1: # print(-1) # exit() # elif black_present == 0 and white_present == 1: # print(0) # exit() # elif black_present == 1 and white_present == 0: # print(m) # exit() # # elif m == 1: # white_present = 0 # black_present = 0 # for i in range(n): # if grid[i][0] == 'B': # black_present = 1 # if grid[i][0] == 'W': # white_present = 1 # if black_present == 1 and white_present == 1: # print(-1) # exit() # elif black_present == 0 and white_present == 1: # print(0) # exit() # elif black_present == 1 and white_present == 0: # print(n) # exit() # # else: for i in range(n): first_black = 0 first_white = 0 second_black = 0 for j in range(m): if grid[i][j] == 'B': if first_black == 0: first_black = 1 elif first_white == 1: second_black = 1 break if grid[i][j] == 'W': if first_black == 1: first_white = 1 if first_black == 1 and first_white == 1 and second_black == 1: print(-1) exit() for j in range(m): first_black = 0 first_white = 0 second_black = 0 for i in range(n): if grid[i][j] == 'B': if first_black == 0: first_black = 1 elif first_white == 1: second_black = 1 break if grid[i][j] == 'W': if first_black == 1: first_white = 1 if first_black == 1 and first_white == 1 and second_black == 1: print(-1) exit() reachable_table = [] ans = 0 for i in range(n): reachable_table.append([0]*m) for i in range(n): for j in range(m): if reachable_table[i][j] == 0 and grid[i][j] == 'B': ans += 1 make_reachable(i,j) print(ans) ```
104,589
Provide tags and a correct Python 3 solution for this coding contest problem. A monopole magnet is a magnet that only has one pole, either north or south. They don't actually exist since real magnets have two poles, but this is a programming contest problem, so we don't care. There is an n× m grid. Initially, you may place some north magnets and some south magnets into the cells. You are allowed to place as many magnets as you like, even multiple in the same cell. An operation is performed as follows. Choose a north magnet and a south magnet to activate. If they are in the same row or the same column and they occupy different cells, then the north magnet moves one unit closer to the south magnet. Otherwise, if they occupy the same cell or do not share a row or column, then nothing changes. Note that the south magnets are immovable. Each cell of the grid is colored black or white. Let's consider ways to place magnets in the cells so that the following conditions are met. 1. There is at least one south magnet in every row and every column. 2. If a cell is colored black, then it is possible for a north magnet to occupy this cell after some sequence of operations from the initial placement. 3. If a cell is colored white, then it is impossible for a north magnet to occupy this cell after some sequence of operations from the initial placement. Determine if it is possible to place magnets such that these conditions are met. If it is possible, find the minimum number of north magnets required (there are no requirements on the number of south magnets). Input The first line contains two integers n and m (1≤ n,m≤ 1000) — the number of rows and the number of columns, respectively. The next n lines describe the coloring. The i-th of these lines contains a string of length m, where the j-th character denotes the color of the cell in row i and column j. The characters "#" and "." represent black and white, respectively. It is guaranteed, that the string will not contain any other characters. Output Output a single integer, the minimum possible number of north magnets required. If there is no placement of magnets that satisfies all conditions, print a single integer -1. Examples Input 3 3 .#. ### ##. Output 1 Input 4 2 ## .# .# ## Output -1 Input 4 5 ....# ####. .###. .#... Output 2 Input 2 1 . # Output -1 Input 3 5 ..... ..... ..... Output 0 Note In the first test, here is an example placement of magnets: <image> In the second test, we can show that no required placement of magnets exists. Here are three example placements that fail to meet the requirements. The first example violates rule 3 since we can move the north magnet down onto a white square. The second example violates rule 2 since we cannot move the north magnet to the bottom-left black square by any sequence of operations. The third example violates rule 1 since there is no south magnet in the first column. <image> In the third test, here is an example placement of magnets. We can show that there is no required placement of magnets with fewer north magnets. <image> In the fourth test, we can show that no required placement of magnets exists. Here are two example placements that fail to meet the requirements. The first example violates rule 1 since there is no south magnet in the first row. The second example violates rules 1 and 3 since there is no south magnet in the second row and we can move the north magnet up one unit onto a white square. <image> In the fifth test, we can put the south magnet in each cell and no north magnets. Because there are no black cells, it will be a correct placement. Tags: constructive algorithms, dfs and similar, dsu, graphs Correct Solution: ``` h, w = map(int, input().split()) b = [list(input()) for _ in range(h)] cnt_mx = 0 all_white_row = 0 for hi in range(h): prev = "." cnt = 0 for wi in range(w): if b[hi][wi] != prev: cnt += 1 prev = b[hi][wi] if cnt == 0: all_white_row += 1 cnt_mx = max(cnt_mx, cnt) all_white_col = 0 for wi in range(w): prev = "." cnt = 0 for hi in range(h): if b[hi][wi] != prev: cnt += 1 prev = b[hi][wi] if cnt == 0: all_white_col += 1 cnt_mx = max(cnt_mx, cnt) if cnt_mx > 2 or [all_white_col, all_white_row].count(0) == 1: print(-1) exit() d = [(-1, 0), (1, 0), (0, -1), (0, 1)] ans = 0 for hi in range(h): for wi in range(w): if b[hi][wi] == "#": ans += 1 stack = [[hi, wi]] b[hi][wi] = "." while stack: hh, ww = stack.pop() for dh, dw in d: nh = hh + dh nw = ww + dw if 0 <= nh <= h - 1 and 0 <= nw <= w - 1 and b[nh][nw] == "#": b[nh][nw] = "." stack.append([nh, nw]) print(ans) ```
104,590
Provide tags and a correct Python 3 solution for this coding contest problem. A monopole magnet is a magnet that only has one pole, either north or south. They don't actually exist since real magnets have two poles, but this is a programming contest problem, so we don't care. There is an n× m grid. Initially, you may place some north magnets and some south magnets into the cells. You are allowed to place as many magnets as you like, even multiple in the same cell. An operation is performed as follows. Choose a north magnet and a south magnet to activate. If they are in the same row or the same column and they occupy different cells, then the north magnet moves one unit closer to the south magnet. Otherwise, if they occupy the same cell or do not share a row or column, then nothing changes. Note that the south magnets are immovable. Each cell of the grid is colored black or white. Let's consider ways to place magnets in the cells so that the following conditions are met. 1. There is at least one south magnet in every row and every column. 2. If a cell is colored black, then it is possible for a north magnet to occupy this cell after some sequence of operations from the initial placement. 3. If a cell is colored white, then it is impossible for a north magnet to occupy this cell after some sequence of operations from the initial placement. Determine if it is possible to place magnets such that these conditions are met. If it is possible, find the minimum number of north magnets required (there are no requirements on the number of south magnets). Input The first line contains two integers n and m (1≤ n,m≤ 1000) — the number of rows and the number of columns, respectively. The next n lines describe the coloring. The i-th of these lines contains a string of length m, where the j-th character denotes the color of the cell in row i and column j. The characters "#" and "." represent black and white, respectively. It is guaranteed, that the string will not contain any other characters. Output Output a single integer, the minimum possible number of north magnets required. If there is no placement of magnets that satisfies all conditions, print a single integer -1. Examples Input 3 3 .#. ### ##. Output 1 Input 4 2 ## .# .# ## Output -1 Input 4 5 ....# ####. .###. .#... Output 2 Input 2 1 . # Output -1 Input 3 5 ..... ..... ..... Output 0 Note In the first test, here is an example placement of magnets: <image> In the second test, we can show that no required placement of magnets exists. Here are three example placements that fail to meet the requirements. The first example violates rule 3 since we can move the north magnet down onto a white square. The second example violates rule 2 since we cannot move the north magnet to the bottom-left black square by any sequence of operations. The third example violates rule 1 since there is no south magnet in the first column. <image> In the third test, here is an example placement of magnets. We can show that there is no required placement of magnets with fewer north magnets. <image> In the fourth test, we can show that no required placement of magnets exists. Here are two example placements that fail to meet the requirements. The first example violates rule 1 since there is no south magnet in the first row. The second example violates rules 1 and 3 since there is no south magnet in the second row and we can move the north magnet up one unit onto a white square. <image> In the fifth test, we can put the south magnet in each cell and no north magnets. Because there are no black cells, it will be a correct placement. Tags: constructive algorithms, dfs and similar, dsu, graphs Correct Solution: ``` import sys import math from collections import deque input = sys.stdin.buffer.readline def BFS(x,y): q = deque() q.append([x,y]) visited[x][y] = 1 while len(q)>0: x,y = q.popleft() if graph[min(x+1,n-1)][y] =='#' and visited[min(x+1,n-1)][y]==0: visited[x+1][y] = 1 q.append([x+1,y]) if graph[max(x-1,0)][y] =='#' and visited[max(x-1,0)][y]==0: visited[x-1][y] = 1 q.append([x-1,y]) if graph[x][min(y+1,m-1)] =='#' and visited[x][min(y+1,m-1)]==0: visited[x][y+1] = 1 q.append([x,y+1]) if graph[x][max(y-1,0)]=='#' and visited[x][max(y-1,0)]==0: visited[x][y-1] = 1 q.append([x,y-1]) n,m = map(int,input().split()) graph = [0]*n for i in range(n): graph[i] = list(map(chr,list(input().strip()))) #print(graph) xx = 0 for i in range(n): x = 0 for j in range(m): if graph[i][j] == '#': if x==2: print(-1) exit(0) else: x=1 else: if x==1: x=2 if x==0: xx = 1 #print(xx) for i in range(m): x = 0 for j in range(n): if graph[j][i] == '#': if x==2: print(-1) exit(0) else: x=1 else: if x==1: x=2 if x==0 and xx==0: print(-1) exit(0) elif x==0: xx = 2 #print(xx) if xx == 1: print(-1) exit(0) visited = [[0 for _ in range(m)] for _ in range(n)] count=0 for i in range(n): for j in range(m): if graph[i][j]=='#' and visited[i][j]==0: count+=1 BFS(i,j) print(count) ```
104,591
Provide tags and a correct Python 3 solution for this coding contest problem. A monopole magnet is a magnet that only has one pole, either north or south. They don't actually exist since real magnets have two poles, but this is a programming contest problem, so we don't care. There is an n× m grid. Initially, you may place some north magnets and some south magnets into the cells. You are allowed to place as many magnets as you like, even multiple in the same cell. An operation is performed as follows. Choose a north magnet and a south magnet to activate. If they are in the same row or the same column and they occupy different cells, then the north magnet moves one unit closer to the south magnet. Otherwise, if they occupy the same cell or do not share a row or column, then nothing changes. Note that the south magnets are immovable. Each cell of the grid is colored black or white. Let's consider ways to place magnets in the cells so that the following conditions are met. 1. There is at least one south magnet in every row and every column. 2. If a cell is colored black, then it is possible for a north magnet to occupy this cell after some sequence of operations from the initial placement. 3. If a cell is colored white, then it is impossible for a north magnet to occupy this cell after some sequence of operations from the initial placement. Determine if it is possible to place magnets such that these conditions are met. If it is possible, find the minimum number of north magnets required (there are no requirements on the number of south magnets). Input The first line contains two integers n and m (1≤ n,m≤ 1000) — the number of rows and the number of columns, respectively. The next n lines describe the coloring. The i-th of these lines contains a string of length m, where the j-th character denotes the color of the cell in row i and column j. The characters "#" and "." represent black and white, respectively. It is guaranteed, that the string will not contain any other characters. Output Output a single integer, the minimum possible number of north magnets required. If there is no placement of magnets that satisfies all conditions, print a single integer -1. Examples Input 3 3 .#. ### ##. Output 1 Input 4 2 ## .# .# ## Output -1 Input 4 5 ....# ####. .###. .#... Output 2 Input 2 1 . # Output -1 Input 3 5 ..... ..... ..... Output 0 Note In the first test, here is an example placement of magnets: <image> In the second test, we can show that no required placement of magnets exists. Here are three example placements that fail to meet the requirements. The first example violates rule 3 since we can move the north magnet down onto a white square. The second example violates rule 2 since we cannot move the north magnet to the bottom-left black square by any sequence of operations. The third example violates rule 1 since there is no south magnet in the first column. <image> In the third test, here is an example placement of magnets. We can show that there is no required placement of magnets with fewer north magnets. <image> In the fourth test, we can show that no required placement of magnets exists. Here are two example placements that fail to meet the requirements. The first example violates rule 1 since there is no south magnet in the first row. The second example violates rules 1 and 3 since there is no south magnet in the second row and we can move the north magnet up one unit onto a white square. <image> In the fifth test, we can put the south magnet in each cell and no north magnets. Because there are no black cells, it will be a correct placement. Tags: constructive algorithms, dfs and similar, dsu, graphs Correct Solution: ``` from collections import deque def valid() : #check rows rows = 0 cols = 0 for r in adj : white = False black = False for col in r : if(col == '#' and white and black) : return False if(col == '#') : black = True if(col == '.' and black) : white = True rows += 1 if not (white or black) else 0 #check cols for j in range(m) : white = False black = False for i in range(n) : if(adj[i][j] == '#' and white and black) : return False if(adj[i][j] == '#') : black = True if(adj[i][j] == '.' and black) : white = True cols += 1 if not (white or black) else 0 return (rows == 0 and cols == 0) or (rows > 0 and cols > 0) def check(r, c) : return r >= 0 and r < n and c >= 0 and c < m and adj[r][c] == '#' and (not vis[r][c]) def dfs(r,c) : vis[r][c] = True for i in range(4) : if check(r + dx[i], c + dy[i]) : dfs(r + dx[i], c + dy[i]) def bfs(r,c) : vis[r][c] = True q = deque() q.append((r,c)) while(len(q) != 0) : t = q.popleft() for i in range(4) : nr = t[0] + dx[i] nc = t[1] + dy[i] if check(nr,nc) : vis[nr][nc] = True q.append((nr,nc)) def cc() : cnt = 0 for i in range(n) : for j in range(m) : if((not vis[i][j]) and adj[i][j] == '#') : cnt += 1 bfs(i,j) return cnt n,m = map(int,input().split()) adj = [] for _ in range(n) : adj.append(input()) vis = [[False] * m for _ in range(n)] dx = [1, -1, 0, 0] dy = [0, 0, 1, -1] print(-1 if not(valid()) else cc()) ```
104,592
Provide tags and a correct Python 3 solution for this coding contest problem. A monopole magnet is a magnet that only has one pole, either north or south. They don't actually exist since real magnets have two poles, but this is a programming contest problem, so we don't care. There is an n× m grid. Initially, you may place some north magnets and some south magnets into the cells. You are allowed to place as many magnets as you like, even multiple in the same cell. An operation is performed as follows. Choose a north magnet and a south magnet to activate. If they are in the same row or the same column and they occupy different cells, then the north magnet moves one unit closer to the south magnet. Otherwise, if they occupy the same cell or do not share a row or column, then nothing changes. Note that the south magnets are immovable. Each cell of the grid is colored black or white. Let's consider ways to place magnets in the cells so that the following conditions are met. 1. There is at least one south magnet in every row and every column. 2. If a cell is colored black, then it is possible for a north magnet to occupy this cell after some sequence of operations from the initial placement. 3. If a cell is colored white, then it is impossible for a north magnet to occupy this cell after some sequence of operations from the initial placement. Determine if it is possible to place magnets such that these conditions are met. If it is possible, find the minimum number of north magnets required (there are no requirements on the number of south magnets). Input The first line contains two integers n and m (1≤ n,m≤ 1000) — the number of rows and the number of columns, respectively. The next n lines describe the coloring. The i-th of these lines contains a string of length m, where the j-th character denotes the color of the cell in row i and column j. The characters "#" and "." represent black and white, respectively. It is guaranteed, that the string will not contain any other characters. Output Output a single integer, the minimum possible number of north magnets required. If there is no placement of magnets that satisfies all conditions, print a single integer -1. Examples Input 3 3 .#. ### ##. Output 1 Input 4 2 ## .# .# ## Output -1 Input 4 5 ....# ####. .###. .#... Output 2 Input 2 1 . # Output -1 Input 3 5 ..... ..... ..... Output 0 Note In the first test, here is an example placement of magnets: <image> In the second test, we can show that no required placement of magnets exists. Here are three example placements that fail to meet the requirements. The first example violates rule 3 since we can move the north magnet down onto a white square. The second example violates rule 2 since we cannot move the north magnet to the bottom-left black square by any sequence of operations. The third example violates rule 1 since there is no south magnet in the first column. <image> In the third test, here is an example placement of magnets. We can show that there is no required placement of magnets with fewer north magnets. <image> In the fourth test, we can show that no required placement of magnets exists. Here are two example placements that fail to meet the requirements. The first example violates rule 1 since there is no south magnet in the first row. The second example violates rules 1 and 3 since there is no south magnet in the second row and we can move the north magnet up one unit onto a white square. <image> In the fifth test, we can put the south magnet in each cell and no north magnets. Because there are no black cells, it will be a correct placement. Tags: constructive algorithms, dfs and similar, dsu, graphs Correct Solution: ``` from collections import deque def BFS(graph, i, j, n, m): Q = deque([]) vis = set() vis.add((i, j)) Q.append((i, j)) neigh = [(1, 0), (-1, 0), (0, 1), (0, -1)] while len(Q): curr = Q.popleft() i = curr[0]; j = curr[1] graph[i][j] = '.' for ne in neigh: x = ne[0]+i; y = ne[1]+j if 0 <= x < n and 0<= y < m and graph[x][y] == '#': if (x, y) not in vis: Q.append((x, y)) vis.add((x, y)) return graph class UnionFind: def __init__(self, N): self.parent = [i for i in range(N)] self.size = [1 for _ in range(N)] def find(self, x): if self.parent[x] == x: return x else: return self.find(self.parent[x]) def union(self, x, y): px = self.find(x) py = self.find(y) if px == py: return if self.size[px] < self.size[py]: self.parent[px] = py self.size[py] += self.size[px] else: self.parent[py] = px self.size[px] += self.size[py] def same(self, x, y): return self.find(x) == self.find(y) N,M = map(int,input().split()) grid=[[v for v in input()] for _ in range(N)] all_white_row=0 all_white_col=0 for n in range(N): r=all(v=="." for v in grid[n]) all_white_row+= 1 if r else 0 for m in range(M): r= all(grid[i][m]=="." for i in range(N)) all_white_col+= 1 if r else 0 seq_in_each_row=1 seq_in_each_col=1 empR=0 empC=0 for i in range(N): flag=0 for j in range(M): if grid[i][j]=="#": if flag==1: if grid[i][j-1]!="#": seq_in_each_row=0 break else: flag=1 if flag==0: empR+=1 for j in range(M): flag=0 for i in range(N): if grid[i][j]=="#": if flag==1: if grid[i-1][j]!="#": seq_in_each_col=0 break else: flag=1 if flag==0: empC+=1 #for n in range(N): # r= len([v for v in "".join(grid[n]).split(".") if len(v)!=0]) # if r==0: # continue # seq_in_each_row*=(r==1) #for m in range(M): # r= len([v for v in "".join([grid[i][m] for i in range(N)]).split(".") if len(v)!=0]) # if r==0: # continue # seq_in_each_col*=(r==1) # if seq_in_each_col*seq_in_each_row==0: print(-1) exit() assert all_white_col==empC and all_white_row==empR if not((all_white_col==0 and all_white_row==0) or (all_white_row>=1 and all_white_col>=1)): print(-1) exit() UN=UnionFind(N*M) DX=[0,1] DY=[1,0] def isIn(n,m): return 0<=n<N and 0<=m<M for n in range(N): for m in range(M): if grid[n][m]==".": continue for dx,dy in zip(DX,DY): nn=n+dx mm=m+dy if isIn(nn,mm) and grid[nn][mm]=="#": UN.union(n*M+m,nn*M+mm) parent=set() for n in range(N): for m in range(M): if grid[n][m]=="#": parent.add(UN.parent[n*M+m]) ans=0 for i in range(N): for j in range(M): if grid[i][j]=="#": ans+=1 grid = BFS(grid,i,j,N,M) #assert ans==len(parent) print(ans) ```
104,593
Provide tags and a correct Python 3 solution for this coding contest problem. A monopole magnet is a magnet that only has one pole, either north or south. They don't actually exist since real magnets have two poles, but this is a programming contest problem, so we don't care. There is an n× m grid. Initially, you may place some north magnets and some south magnets into the cells. You are allowed to place as many magnets as you like, even multiple in the same cell. An operation is performed as follows. Choose a north magnet and a south magnet to activate. If they are in the same row or the same column and they occupy different cells, then the north magnet moves one unit closer to the south magnet. Otherwise, if they occupy the same cell or do not share a row or column, then nothing changes. Note that the south magnets are immovable. Each cell of the grid is colored black or white. Let's consider ways to place magnets in the cells so that the following conditions are met. 1. There is at least one south magnet in every row and every column. 2. If a cell is colored black, then it is possible for a north magnet to occupy this cell after some sequence of operations from the initial placement. 3. If a cell is colored white, then it is impossible for a north magnet to occupy this cell after some sequence of operations from the initial placement. Determine if it is possible to place magnets such that these conditions are met. If it is possible, find the minimum number of north magnets required (there are no requirements on the number of south magnets). Input The first line contains two integers n and m (1≤ n,m≤ 1000) — the number of rows and the number of columns, respectively. The next n lines describe the coloring. The i-th of these lines contains a string of length m, where the j-th character denotes the color of the cell in row i and column j. The characters "#" and "." represent black and white, respectively. It is guaranteed, that the string will not contain any other characters. Output Output a single integer, the minimum possible number of north magnets required. If there is no placement of magnets that satisfies all conditions, print a single integer -1. Examples Input 3 3 .#. ### ##. Output 1 Input 4 2 ## .# .# ## Output -1 Input 4 5 ....# ####. .###. .#... Output 2 Input 2 1 . # Output -1 Input 3 5 ..... ..... ..... Output 0 Note In the first test, here is an example placement of magnets: <image> In the second test, we can show that no required placement of magnets exists. Here are three example placements that fail to meet the requirements. The first example violates rule 3 since we can move the north magnet down onto a white square. The second example violates rule 2 since we cannot move the north magnet to the bottom-left black square by any sequence of operations. The third example violates rule 1 since there is no south magnet in the first column. <image> In the third test, here is an example placement of magnets. We can show that there is no required placement of magnets with fewer north magnets. <image> In the fourth test, we can show that no required placement of magnets exists. Here are two example placements that fail to meet the requirements. The first example violates rule 1 since there is no south magnet in the first row. The second example violates rules 1 and 3 since there is no south magnet in the second row and we can move the north magnet up one unit onto a white square. <image> In the fifth test, we can put the south magnet in each cell and no north magnets. Because there are no black cells, it will be a correct placement. Tags: constructive algorithms, dfs and similar, dsu, graphs Correct Solution: ``` class UnionFind: def __init__(self, n): self.parent = list(range(n)) def find(self, a): #return parent of a. a and b are in same set if they have same parent acopy = a while a != self.parent[a]: a = self.parent[a] while acopy != a: #path compression self.parent[acopy], acopy = a, self.parent[acopy] return a def union(self, a, b): #union a and b self.parent[self.find(b)] = self.find(a) # ##Usage: (note that all index references are 0-indexed) #n=100 #number of items, indexed from 0 to n-1 #uf=UnionFind(n) #assert uf.find(85)!=uf.find(4) #uf.union(85,4) #assert uf.find(85)==uf.find(4) def convertCoordToInt(i,j,n,m): #for union find return i*m+j def main(): #Put a South on every '#' #Use DSU to check how many groups of connected '#' there are, #And ensure that it is impossible to reach all '.' #If there is an empty row, there must be at least 1 empty column to put South at intersection. #Same logic for empty column, unless there are no '#'. n,m=readIntArr() arr=[] for _ in range(n): arr.append(input()) rows=[[None,None] for _ in range(n)] #[earliest '#' column, latest '#' column] columns=[[None,None] for _ in range(m)] southCnt=0 for i in range(n): for j in range(m): if arr[i][j]=='#': southCnt+=1 if rows[i][0]==None: rows[i]=[j,j] else: rows[i][0]=min(rows[i][0],j) rows[i][1]=max(rows[i][1],j) if columns[j][0]==None: columns[j]=[i,i] else: columns[j][0]=min(columns[j][0],i) columns[j][1]=max(columns[j][1],i) if southCnt==0: #no '#' so no need any Norths print(0) return #Unoccupied row and column counts check uRowCnts=0 uColCnts=0 for i in range(n): if rows[i][0]==None: uRowCnts+=1 for j in range(m): if columns[j][0]==None: uColCnts+=1 # print(uRowCnts,uColCnts)## if not ((uRowCnts==0 and uColCnts==0) or (uRowCnts!=0 and uColCnts!=0)): #1 of them is 0 print(-1) return uf=UnionFind(n*m) for i in range(n): for j in range(m): if arr[i][j]=='#': coord1=convertCoordToInt(i,j,n,m) parent=uf.find(coord1) #dfs st=[[i,j]] # print('next stack')#### while st: ii,jj=st.pop() minCol,maxCol=rows[ii] minRow,maxRow=columns[jj] #### # print('ii:{} jj:{} minCol:{} maxCol:{} minRow:{} maxRow:{}'.format(ii,jj,minCol,maxCol,minRow,maxRow)) possibleCoords=[] if minRow<ii: possibleCoords.append([ii-1,jj]) if maxRow>ii: possibleCoords.append([ii+1,jj]) if minCol<jj: possibleCoords.append([ii,jj-1]) if maxCol>jj: possibleCoords.append([ii,jj+1]) #### # print('possibleCoords:{}'.format(possibleCoords)) for iii,jjj in possibleCoords: if arr[iii][jjj]=='#': coord2=convertCoordToInt(iii,jjj,n,m) parent2=uf.find(coord2) if parent!=parent2: #iii,jjj is not yet visited uf.union(coord1,coord2) st.append([iii,jjj]) parent=uf.find(coord1) # print('({}) {} ({}) {}'.format((i,j),uf.find(convertCoordToInt(i,j,n,m)), # (iii,jjj),uf.find(convertCoordToInt(iii,jjj,n,m)))) #### else: #'.' impossible print(-1) return groups=set() for i in range(n): for j in range(m): if arr[i][j]=='#': groups.add(uf.find(convertCoordToInt(i,j,n,m))) print(len(groups)) #### # print('uRowCnts:{} uColCnts:{}'.format(uRowCnts,uColCnts)) #### # print('rows:{}\ncols:{}'.format(rows,columns)) # group2=[[-1 for _ in range(n)] for __ in range(m)] # for i in range(n): # for j in range(m): # if arr[i][j]=='#': # group2[i][j]=uf.find(convertCoordToInt(i,j,n,m)) # multiLineArrayOfArraysPrint(group2) return #import sys #input=sys.stdin.buffer.readline #FOR READING PURE INTEGER INPUTS (space separation ok) import sys input=lambda: sys.stdin.readline().rstrip("\r\n") #FOR READING STRING/TEXT INPUTS. def oneLineArrayPrint(arr): print(' '.join([str(x) for x in arr])) def multiLineArrayPrint(arr): print('\n'.join([str(x) for x in arr])) def multiLineArrayOfArraysPrint(arr): print('\n'.join([' '.join([str(x) for x in y]) for y in arr])) def readIntArr(): return [int(x) for x in input().split()] inf=float('inf') MOD=10**9+7 main() ```
104,594
Provide tags and a correct Python 2 solution for this coding contest problem. A monopole magnet is a magnet that only has one pole, either north or south. They don't actually exist since real magnets have two poles, but this is a programming contest problem, so we don't care. There is an n× m grid. Initially, you may place some north magnets and some south magnets into the cells. You are allowed to place as many magnets as you like, even multiple in the same cell. An operation is performed as follows. Choose a north magnet and a south magnet to activate. If they are in the same row or the same column and they occupy different cells, then the north magnet moves one unit closer to the south magnet. Otherwise, if they occupy the same cell or do not share a row or column, then nothing changes. Note that the south magnets are immovable. Each cell of the grid is colored black or white. Let's consider ways to place magnets in the cells so that the following conditions are met. 1. There is at least one south magnet in every row and every column. 2. If a cell is colored black, then it is possible for a north magnet to occupy this cell after some sequence of operations from the initial placement. 3. If a cell is colored white, then it is impossible for a north magnet to occupy this cell after some sequence of operations from the initial placement. Determine if it is possible to place magnets such that these conditions are met. If it is possible, find the minimum number of north magnets required (there are no requirements on the number of south magnets). Input The first line contains two integers n and m (1≤ n,m≤ 1000) — the number of rows and the number of columns, respectively. The next n lines describe the coloring. The i-th of these lines contains a string of length m, where the j-th character denotes the color of the cell in row i and column j. The characters "#" and "." represent black and white, respectively. It is guaranteed, that the string will not contain any other characters. Output Output a single integer, the minimum possible number of north magnets required. If there is no placement of magnets that satisfies all conditions, print a single integer -1. Examples Input 3 3 .#. ### ##. Output 1 Input 4 2 ## .# .# ## Output -1 Input 4 5 ....# ####. .###. .#... Output 2 Input 2 1 . # Output -1 Input 3 5 ..... ..... ..... Output 0 Note In the first test, here is an example placement of magnets: <image> In the second test, we can show that no required placement of magnets exists. Here are three example placements that fail to meet the requirements. The first example violates rule 3 since we can move the north magnet down onto a white square. The second example violates rule 2 since we cannot move the north magnet to the bottom-left black square by any sequence of operations. The third example violates rule 1 since there is no south magnet in the first column. <image> In the third test, here is an example placement of magnets. We can show that there is no required placement of magnets with fewer north magnets. <image> In the fourth test, we can show that no required placement of magnets exists. Here are two example placements that fail to meet the requirements. The first example violates rule 1 since there is no south magnet in the first row. The second example violates rules 1 and 3 since there is no south magnet in the second row and we can move the north magnet up one unit onto a white square. <image> In the fifth test, we can put the south magnet in each cell and no north magnets. Because there are no black cells, it will be a correct placement. Tags: constructive algorithms, dfs and similar, dsu, graphs Correct Solution: ``` from sys import stdin, stdout from collections import Counter, defaultdict from itertools import permutations, combinations raw_input = stdin.readline pr = stdout.write def fun(x): return 1*(x=='#') def in_num(): return int(raw_input()) def in_arr(): return map(fun,raw_input().strip()) def pr_num(n): stdout.write(str(n)+'\n') def pr_arr(arr): pr(' '.join(map(str,arr))+'\n') # fast read function for total integer input def inp(): # this function returns whole input of # space/line seperated integers # Use Ctrl+D to flush stdin. return map(int,stdin.read().split()) range = xrange # not for python 3.0+ n,m=map(int,raw_input().split()) l=[] sm=0 for i in range(n): l.append(in_arr()) sm+=sum(l[-1]) if sm==0: pr_num(0) exit() if n==1 or m==1: if sm!=n*m: pr_num(-1) else: pr_num(1) exit() f1,f2=0,0 for i in range(n): c=0 sm=l[i][-1] for j in range(m-1): if l[i][j]: c=1 sm+=l[i][j] if l[i][j]==0 and c and l[i][j+1]: pr_num(-1) exit() if sm==0: f1=1 for j in range(m): f=0 sm=l[-1][j] for i in range(n-1): sm+=l[i][j] if l[i][j]==1: f=1 if l[i][j]==0 and f and l[i+1][j]==1: pr_num(-1) exit() if sm==0: f2=1 if f1^f2: pr_num(-1) exit() vis=[[0 for i in range(m)] for j in range(n)] ans=0 move=[(1,0),(-1,0),(0,1),(0,-1)] f=0 for i in range(n): for j in range(m): if l[i][j] and not vis[i][j]: #print 'x',i,j vis[i][j]=1 q=[(i,j)] ans+=1 while q: x,y=q.pop() #print x,y for x1,y1 in move: x2=x1+x y2=y1+y if x2>=0 and x2<n and y2>=0 and y2<m: if l[x2][y2] and not vis[x2][y2]: vis[x2][y2]=1 q.append((x2,y2)) pr_num(ans) ```
104,595
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. A monopole magnet is a magnet that only has one pole, either north or south. They don't actually exist since real magnets have two poles, but this is a programming contest problem, so we don't care. There is an n× m grid. Initially, you may place some north magnets and some south magnets into the cells. You are allowed to place as many magnets as you like, even multiple in the same cell. An operation is performed as follows. Choose a north magnet and a south magnet to activate. If they are in the same row or the same column and they occupy different cells, then the north magnet moves one unit closer to the south magnet. Otherwise, if they occupy the same cell or do not share a row or column, then nothing changes. Note that the south magnets are immovable. Each cell of the grid is colored black or white. Let's consider ways to place magnets in the cells so that the following conditions are met. 1. There is at least one south magnet in every row and every column. 2. If a cell is colored black, then it is possible for a north magnet to occupy this cell after some sequence of operations from the initial placement. 3. If a cell is colored white, then it is impossible for a north magnet to occupy this cell after some sequence of operations from the initial placement. Determine if it is possible to place magnets such that these conditions are met. If it is possible, find the minimum number of north magnets required (there are no requirements on the number of south magnets). Input The first line contains two integers n and m (1≤ n,m≤ 1000) — the number of rows and the number of columns, respectively. The next n lines describe the coloring. The i-th of these lines contains a string of length m, where the j-th character denotes the color of the cell in row i and column j. The characters "#" and "." represent black and white, respectively. It is guaranteed, that the string will not contain any other characters. Output Output a single integer, the minimum possible number of north magnets required. If there is no placement of magnets that satisfies all conditions, print a single integer -1. Examples Input 3 3 .#. ### ##. Output 1 Input 4 2 ## .# .# ## Output -1 Input 4 5 ....# ####. .###. .#... Output 2 Input 2 1 . # Output -1 Input 3 5 ..... ..... ..... Output 0 Note In the first test, here is an example placement of magnets: <image> In the second test, we can show that no required placement of magnets exists. Here are three example placements that fail to meet the requirements. The first example violates rule 3 since we can move the north magnet down onto a white square. The second example violates rule 2 since we cannot move the north magnet to the bottom-left black square by any sequence of operations. The third example violates rule 1 since there is no south magnet in the first column. <image> In the third test, here is an example placement of magnets. We can show that there is no required placement of magnets with fewer north magnets. <image> In the fourth test, we can show that no required placement of magnets exists. Here are two example placements that fail to meet the requirements. The first example violates rule 1 since there is no south magnet in the first row. The second example violates rules 1 and 3 since there is no south magnet in the second row and we can move the north magnet up one unit onto a white square. <image> In the fifth test, we can put the south magnet in each cell and no north magnets. Because there are no black cells, it will be a correct placement. Submitted Solution: ``` from sys import exit n, m = map(int, input().split()) a = [tuple(input()) for i in range(n)] whiteline = False whilecolumne = False howmany = 0 ar = [[0] * m for i in range(n)] for x in range(n): lastelem = '.' shag = 0 for y in range(m): elem = a[x][y] if elem == '#': if lastelem != elem: newnam = howmany + 1 if x!= 0: if ar[x-1][y] != 0: newnam = ar[x-1][y] elif ar[x][y] != 0: newnam = ar[x][y] else: howmany += 1 elif ar[x][y] != 0: newnam = ar[x][y] else: howmany += 1 x1 = x + 1 y1 = y ar[x][y] = newnam if x1 != n: while y1 != -1 and a[x1][y1] == "#": ar[x1][y1] = newnam y1 -= 1 else: ar[x][y] = ar[x][y-1] if elem != lastelem: shag += 1 lastelem = elem if shag == 0: whiteline = True if shag > 2: print(-1) exit() for y in range(m): lastelem = '.' shag = 0 for x in range(n): elem = a[x][y] if elem != lastelem: shag += 1 lastelem = elem if shag == 0: whilecolumne = True if shag > 2: print(-1) exit() if whilecolumne ^ whiteline: print(-1) exit() print(howmany) ``` Yes
104,596
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. A monopole magnet is a magnet that only has one pole, either north or south. They don't actually exist since real magnets have two poles, but this is a programming contest problem, so we don't care. There is an n× m grid. Initially, you may place some north magnets and some south magnets into the cells. You are allowed to place as many magnets as you like, even multiple in the same cell. An operation is performed as follows. Choose a north magnet and a south magnet to activate. If they are in the same row or the same column and they occupy different cells, then the north magnet moves one unit closer to the south magnet. Otherwise, if they occupy the same cell or do not share a row or column, then nothing changes. Note that the south magnets are immovable. Each cell of the grid is colored black or white. Let's consider ways to place magnets in the cells so that the following conditions are met. 1. There is at least one south magnet in every row and every column. 2. If a cell is colored black, then it is possible for a north magnet to occupy this cell after some sequence of operations from the initial placement. 3. If a cell is colored white, then it is impossible for a north magnet to occupy this cell after some sequence of operations from the initial placement. Determine if it is possible to place magnets such that these conditions are met. If it is possible, find the minimum number of north magnets required (there are no requirements on the number of south magnets). Input The first line contains two integers n and m (1≤ n,m≤ 1000) — the number of rows and the number of columns, respectively. The next n lines describe the coloring. The i-th of these lines contains a string of length m, where the j-th character denotes the color of the cell in row i and column j. The characters "#" and "." represent black and white, respectively. It is guaranteed, that the string will not contain any other characters. Output Output a single integer, the minimum possible number of north magnets required. If there is no placement of magnets that satisfies all conditions, print a single integer -1. Examples Input 3 3 .#. ### ##. Output 1 Input 4 2 ## .# .# ## Output -1 Input 4 5 ....# ####. .###. .#... Output 2 Input 2 1 . # Output -1 Input 3 5 ..... ..... ..... Output 0 Note In the first test, here is an example placement of magnets: <image> In the second test, we can show that no required placement of magnets exists. Here are three example placements that fail to meet the requirements. The first example violates rule 3 since we can move the north magnet down onto a white square. The second example violates rule 2 since we cannot move the north magnet to the bottom-left black square by any sequence of operations. The third example violates rule 1 since there is no south magnet in the first column. <image> In the third test, here is an example placement of magnets. We can show that there is no required placement of magnets with fewer north magnets. <image> In the fourth test, we can show that no required placement of magnets exists. Here are two example placements that fail to meet the requirements. The first example violates rule 1 since there is no south magnet in the first row. The second example violates rules 1 and 3 since there is no south magnet in the second row and we can move the north magnet up one unit onto a white square. <image> In the fifth test, we can put the south magnet in each cell and no north magnets. Because there are no black cells, it will be a correct placement. Submitted Solution: ``` def check(s): t=[0]+s+[0] flag=0 for i in t: if flag==0: if i==1: flag=1 elif flag==1: if i==0: flag=2 elif flag==2: if i==1: return False return True h,w=map(int,input().split()) grid=[] for i in range(h): s=input() b=[] for j in s: if j==".":b.append(0) else:b.append(1) grid.append(b) for i in range(h): if not(check(grid[i])): print(-1) exit() for j in range(w): if not(check([grid[i][j] for i in range(h)])): print(-1) exit() ans=0 hh=[1]*h ww=[1]*w for i in range(h): for j in range(w): if grid[i][j]: stack=[(i,j)] grid[i][j]=0 hh[i]=0 ww[j]=0 for x,y in stack: if 0<x: if grid[x-1][y]: stack.append((x-1,y)) grid[x-1][y]=0 hh[x-1]=ww[y]=0 if x<h-1: if grid[x+1][y]: stack.append((x+1,y)) grid[x+1][y]=0 hh[x+1]=ww[y]=0 if 0<y: if grid[x][y-1]: stack.append((x,y-1)) grid[x][y-1]=0 hh[x]=ww[y-1]=0 if y<w-1: if grid[x][y+1]: stack.append((x,y+1)) grid[x][y+1]=0 hh[x]=ww[y+1]=0 ans+=1 if 1 in hh or 1 in ww: if hh.count(1)*ww.count(1)==0: print(-1) exit() print(ans) ``` Yes
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. A monopole magnet is a magnet that only has one pole, either north or south. They don't actually exist since real magnets have two poles, but this is a programming contest problem, so we don't care. There is an n× m grid. Initially, you may place some north magnets and some south magnets into the cells. You are allowed to place as many magnets as you like, even multiple in the same cell. An operation is performed as follows. Choose a north magnet and a south magnet to activate. If they are in the same row or the same column and they occupy different cells, then the north magnet moves one unit closer to the south magnet. Otherwise, if they occupy the same cell or do not share a row or column, then nothing changes. Note that the south magnets are immovable. Each cell of the grid is colored black or white. Let's consider ways to place magnets in the cells so that the following conditions are met. 1. There is at least one south magnet in every row and every column. 2. If a cell is colored black, then it is possible for a north magnet to occupy this cell after some sequence of operations from the initial placement. 3. If a cell is colored white, then it is impossible for a north magnet to occupy this cell after some sequence of operations from the initial placement. Determine if it is possible to place magnets such that these conditions are met. If it is possible, find the minimum number of north magnets required (there are no requirements on the number of south magnets). Input The first line contains two integers n and m (1≤ n,m≤ 1000) — the number of rows and the number of columns, respectively. The next n lines describe the coloring. The i-th of these lines contains a string of length m, where the j-th character denotes the color of the cell in row i and column j. The characters "#" and "." represent black and white, respectively. It is guaranteed, that the string will not contain any other characters. Output Output a single integer, the minimum possible number of north magnets required. If there is no placement of magnets that satisfies all conditions, print a single integer -1. Examples Input 3 3 .#. ### ##. Output 1 Input 4 2 ## .# .# ## Output -1 Input 4 5 ....# ####. .###. .#... Output 2 Input 2 1 . # Output -1 Input 3 5 ..... ..... ..... Output 0 Note In the first test, here is an example placement of magnets: <image> In the second test, we can show that no required placement of magnets exists. Here are three example placements that fail to meet the requirements. The first example violates rule 3 since we can move the north magnet down onto a white square. The second example violates rule 2 since we cannot move the north magnet to the bottom-left black square by any sequence of operations. The third example violates rule 1 since there is no south magnet in the first column. <image> In the third test, here is an example placement of magnets. We can show that there is no required placement of magnets with fewer north magnets. <image> In the fourth test, we can show that no required placement of magnets exists. Here are two example placements that fail to meet the requirements. The first example violates rule 1 since there is no south magnet in the first row. The second example violates rules 1 and 3 since there is no south magnet in the second row and we can move the north magnet up one unit onto a white square. <image> In the fifth test, we can put the south magnet in each cell and no north magnets. Because there are no black cells, it will be a correct placement. Submitted Solution: ``` import os, sys from io import BytesIO, IOBase from types import GeneratorType from bisect import bisect_left, bisect_right from collections import defaultdict as dd, deque as dq, Counter as dc import math, string import heapq as h, time BUFSIZE = 8192 class FastIO(IOBase): newlines = 0 def __init__(self, file): import os self.os = os self._fd = file.fileno() self.buffer = BytesIO() self.writable = "x" in file.mode or "r" not in file.mode self.write = self.buffer.write if self.writable else None def read(self): while True: b = self.os.read(self._fd, max(self.os.fstat(self._fd).st_size, BUFSIZE)) if not b: break ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines = 0 return self.buffer.read() def readline(self): while self.newlines == 0: b = self.os.read(self._fd, max(self.os.fstat(self._fd).st_size, BUFSIZE)) self.newlines = b.count(b"\n") + (not b) ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines -= 1 return self.buffer.readline() def flush(self): if self.writable: self.os.write(self._fd, self.buffer.getvalue()) self.buffer.truncate(0), self.buffer.seek(0) class IOWrapper(IOBase): def __init__(self, file): self.buffer = FastIO(file) self.flush = self.buffer.flush self.writable = self.buffer.writable self.write = lambda s: self.buffer.write(s.encode("ascii")) self.read = lambda: self.buffer.read().decode("ascii") self.readline = lambda: self.buffer.readline().decode("ascii") sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout) input = lambda: sys.stdin.readline().rstrip("\r\n") #start_time = time.time() def getInt(): return int(input()) def getStrs(): return input().split() def getInts(): return list(map(int,input().split())) def getStr(): return input() def listStr(): return list(input()) def getMat(n): return [getInts() for _ in range(n)] def getBin(): return list(map(int,list(input()))) def isInt(s): return '0' <= s[0] <= '9' def ceil_(a,b): return a//b + (a%b > 0) MOD = 10**9 + 7 """ It's possible if there are no dots between hashes The min number = the min number of connected components DSU the points for i in range(1,N+1), for j in range(1,M+1) row i column j is cell i*M + j """ def solve(): def find(a): if a != p[a]: p[a] = find(p[a]) return p[a] def union(a, b): a, b = find(a), find(b) if a == b: return if size[a] > size[b]: a, b = b, a p[a] = b size[b] += size[a] return N, M = getInts() grid = ['.']*(M+2) for _ in range(N): grid += ['.'] + listStr() + ['.'] grid += ['.']*(M+2) N += 2 M += 2 num = N*M bad_row = bad_col = 0 #Check whether it's possible: i.e. whether #.# exists in any row/col for i in range(1,N-1): seen_hash = False seen_dot = False for j in range(1,M-1): if grid[i*M + j] == '#': if seen_dot: return -1 seen_hash = True else: if seen_hash: seen_dot = True if not seen_hash: bad_row = 1 for j in range(1,M-1): seen_hash = False seen_dot = False for i in range(1,N-1): if grid[i*M + j] == '#': if seen_dot: return -1 seen_hash = True else: if seen_hash: seen_dot = True if not seen_hash: bad_col = 1 if bad_row ^ bad_col: return -1 #If we've made it this far, it's possible and we just need to count connected components p = [i for i in range(num)] size = [1]*num for i in range(num-M-1): if grid[i] != '#': p[i] = -i-1 continue if grid[i+1] == '#': union(i,i+1) if grid[i+M] == '#': union(i,i+M) ans = set() for i in range(num-M-1): if p[i] < 0: continue f = find(i) if f != -1: ans.add(f) return len(ans) #for _ in range(getInt()): print(solve()) #solve() #print(time.time()-start_time) ``` Yes
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. A monopole magnet is a magnet that only has one pole, either north or south. They don't actually exist since real magnets have two poles, but this is a programming contest problem, so we don't care. There is an n× m grid. Initially, you may place some north magnets and some south magnets into the cells. You are allowed to place as many magnets as you like, even multiple in the same cell. An operation is performed as follows. Choose a north magnet and a south magnet to activate. If they are in the same row or the same column and they occupy different cells, then the north magnet moves one unit closer to the south magnet. Otherwise, if they occupy the same cell or do not share a row or column, then nothing changes. Note that the south magnets are immovable. Each cell of the grid is colored black or white. Let's consider ways to place magnets in the cells so that the following conditions are met. 1. There is at least one south magnet in every row and every column. 2. If a cell is colored black, then it is possible for a north magnet to occupy this cell after some sequence of operations from the initial placement. 3. If a cell is colored white, then it is impossible for a north magnet to occupy this cell after some sequence of operations from the initial placement. Determine if it is possible to place magnets such that these conditions are met. If it is possible, find the minimum number of north magnets required (there are no requirements on the number of south magnets). Input The first line contains two integers n and m (1≤ n,m≤ 1000) — the number of rows and the number of columns, respectively. The next n lines describe the coloring. The i-th of these lines contains a string of length m, where the j-th character denotes the color of the cell in row i and column j. The characters "#" and "." represent black and white, respectively. It is guaranteed, that the string will not contain any other characters. Output Output a single integer, the minimum possible number of north magnets required. If there is no placement of magnets that satisfies all conditions, print a single integer -1. Examples Input 3 3 .#. ### ##. Output 1 Input 4 2 ## .# .# ## Output -1 Input 4 5 ....# ####. .###. .#... Output 2 Input 2 1 . # Output -1 Input 3 5 ..... ..... ..... Output 0 Note In the first test, here is an example placement of magnets: <image> In the second test, we can show that no required placement of magnets exists. Here are three example placements that fail to meet the requirements. The first example violates rule 3 since we can move the north magnet down onto a white square. The second example violates rule 2 since we cannot move the north magnet to the bottom-left black square by any sequence of operations. The third example violates rule 1 since there is no south magnet in the first column. <image> In the third test, here is an example placement of magnets. We can show that there is no required placement of magnets with fewer north magnets. <image> In the fourth test, we can show that no required placement of magnets exists. Here are two example placements that fail to meet the requirements. The first example violates rule 1 since there is no south magnet in the first row. The second example violates rules 1 and 3 since there is no south magnet in the second row and we can move the north magnet up one unit onto a white square. <image> In the fifth test, we can put the south magnet in each cell and no north magnets. Because there are no black cells, it will be a correct placement. Submitted Solution: ``` import sys input = sys.stdin.readline n, m = map(int, input().split()) l = [''] * n for i in range(n): l[i] = input().strip() works = True rows = [False] * n cols = [False] * m for i in range(n): for j in range(m): if l[i][j] == '#': rows[i] = True cols[j] = True if all(rows) ^ all(cols): works = False for i in range(n): s = l[i] left = -1 right = -1 for j in range(m): if s[j] == '#': if left == -1: left = j right = j for j in range(left + 1, right): if s[j] != '#': works = False for j in range(m): left = -1 right = -1 for i in range(n): if l[i][j] == '#': if left == -1: left = i right = i for i in range(left + 1, right): if l[i][j] != '#': works = False if works: visited = [[False] * m for i in range(n)] out = 0 for i in range(n): for j in range(m): if l[i][j] != '#': visited[i][j] = True for startX in range(n): for startY in range(m): if not visited[startX][startY]: out += 1 visited[startX][startY] = True queue = [(startX, startY)] while queue: x, y = queue.pop() for d in range(4): nX = x + [0,0,-1,1][d] nY = y + [1,-1,0,0][d] if 0 <= nX < n and 0 <= nY < m and not visited[nX][nY]: visited[nX][nY] = True queue.append((nX, nY)) print(out) else: print(-1) ``` Yes
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