text stringlengths 198 433k | conversation_id int64 0 109k |
|---|---|
Provide tags and a correct Python 3 solution for this coding contest problem.
Sereja and his friends went to a picnic. The guys had n soda bottles just for it. Sereja forgot the bottle opener as usual, so the guys had to come up with another way to open bottles.
Sereja knows that the i-th bottle is from brand ai, besides, you can use it to open other bottles of brand bi. You can use one bottle to open multiple other bottles. Sereja can open bottle with opened bottle or closed bottle.
Knowing this, Sereja wants to find out the number of bottles they've got that they won't be able to open in any way. Help him and find this number.
Input
The first line contains integer n (1 ≤ n ≤ 100) — the number of bottles. The next n lines contain the bottles' description. The i-th line contains two integers ai, bi (1 ≤ ai, bi ≤ 1000) — the description of the i-th bottle.
Output
In a single line print a single integer — the answer to the problem.
Examples
Input
4
1 1
2 2
3 3
4 4
Output
4
Input
4
1 2
2 3
3 4
4 1
Output
0
Tags: brute force
Correct Solution:
```
n=int(input())
l=[list(map(int,input().split())) for i in range(n)]
c=0
for i in range(n):
temp=0
for j in range(n):
if l[i][0]==l[j][1] and i!=j:temp+=1
if temp==0:c+=1
print(c)
```
| 94,700 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Sereja and his friends went to a picnic. The guys had n soda bottles just for it. Sereja forgot the bottle opener as usual, so the guys had to come up with another way to open bottles.
Sereja knows that the i-th bottle is from brand ai, besides, you can use it to open other bottles of brand bi. You can use one bottle to open multiple other bottles. Sereja can open bottle with opened bottle or closed bottle.
Knowing this, Sereja wants to find out the number of bottles they've got that they won't be able to open in any way. Help him and find this number.
Input
The first line contains integer n (1 ≤ n ≤ 100) — the number of bottles. The next n lines contain the bottles' description. The i-th line contains two integers ai, bi (1 ≤ ai, bi ≤ 1000) — the description of the i-th bottle.
Output
In a single line print a single integer — the answer to the problem.
Examples
Input
4
1 1
2 2
3 3
4 4
Output
4
Input
4
1 2
2 3
3 4
4 1
Output
0
Tags: brute force
Correct Solution:
```
import sys
from functools import reduce
from collections import Counter
import time
import datetime
from math import sqrt,gcd
# def time_t():
# print("Current date and time: " , datetime.datetime.now())
# print("Current year: ", datetime.date.today().strftime("%Y"))
# print("Month of year: ", datetime.date.today().strftime("%B"))
# print("Week number of the year: ", datetime.date.today().strftime("%W"))
# print("Weekday of the week: ", datetime.date.today().strftime("%w"))
# print("Day of year: ", datetime.date.today().strftime("%j"))
# print("Day of the month : ", datetime.date.today().strftime("%d"))
# print("Day of week: ", datetime.date.today().strftime("%A"))
def ip(): return int(sys.stdin.readline())
def sip(): return sys.stdin.readline()
def mip(): return map(int,sys.stdin.readline().split())
def mips(): return map(str,sys.stdin.readline().split())
def lip(): return list(map(int,sys.stdin.readline().split()))
def matip(n,m):
lst=[]
for i in range(n):
arr = lip()
lst.append(arr)
return lst
def factors(n): # find the factors of a number
return list(set(reduce(list.__add__, ([i, n//i] for i in range(1, int(n**0.5) + 1) if n % i == 0))))
def minJumps(arr, n): #to reach from 0 to n-1 in the array in minimum steps
jumps = [0 for i in range(n)]
if (n == 0) or (arr[0] == 0):
return float('inf')
jumps[0] = 0
for i in range(1, n):
jumps[i] = float('inf')
for j in range(i):
if (i <= j + arr[j]) and (jumps[j] != float('inf')):
jumps[i] = min(jumps[i], jumps[j] + 1)
break
return jumps[n-1]
def dic(arr): # converting list into dict of count
return Counter(arr)
def check_prime(n):
if n<2:
return False
for i in range(2,int(n**(0.5))+1,2):
if n%i==0:
return False
return True
# --------------------------------------------------------- #
# sys.stdin = open('input.txt','r')
# sys.stdout = open('output.txt','w')
# --------------------------------------------------------- #
t = ip()
bottles = []
opened = []
count = 0
for _ in range(t):
a,b = mip()
bottles.append(a)
opened.append(b)
for i in range(t):
if bottles[i] not in opened[:i]:
if bottles[i] not in opened[i+1:]:
count+=1
print(count)
```
| 94,701 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Sereja and his friends went to a picnic. The guys had n soda bottles just for it. Sereja forgot the bottle opener as usual, so the guys had to come up with another way to open bottles.
Sereja knows that the i-th bottle is from brand ai, besides, you can use it to open other bottles of brand bi. You can use one bottle to open multiple other bottles. Sereja can open bottle with opened bottle or closed bottle.
Knowing this, Sereja wants to find out the number of bottles they've got that they won't be able to open in any way. Help him and find this number.
Input
The first line contains integer n (1 ≤ n ≤ 100) — the number of bottles. The next n lines contain the bottles' description. The i-th line contains two integers ai, bi (1 ≤ ai, bi ≤ 1000) — the description of the i-th bottle.
Output
In a single line print a single integer — the answer to the problem.
Examples
Input
4
1 1
2 2
3 3
4 4
Output
4
Input
4
1 2
2 3
3 4
4 1
Output
0
Tags: brute force
Correct Solution:
```
import re
in1 = int(input())
count = 0
bto = []
bco = []
conA = []
conB = []
for _ in range(in1):
inX = [int(x) for x in re.split("\\s", input())]
if inX[0] != inX[1]:
bto.append(inX[0])
bco.append(inX[1])
else:
if inX[0] not in conA:
conA.append(inX[1])
else:
conB.append(inX[1])
for x in conA:
if x not in conB and x not in bco:
count += 1
for x in bto:
if x not in bco and x not in conA:
count += 1
print(count)
```
| 94,702 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Sereja and his friends went to a picnic. The guys had n soda bottles just for it. Sereja forgot the bottle opener as usual, so the guys had to come up with another way to open bottles.
Sereja knows that the i-th bottle is from brand ai, besides, you can use it to open other bottles of brand bi. You can use one bottle to open multiple other bottles. Sereja can open bottle with opened bottle or closed bottle.
Knowing this, Sereja wants to find out the number of bottles they've got that they won't be able to open in any way. Help him and find this number.
Input
The first line contains integer n (1 ≤ n ≤ 100) — the number of bottles. The next n lines contain the bottles' description. The i-th line contains two integers ai, bi (1 ≤ ai, bi ≤ 1000) — the description of the i-th bottle.
Output
In a single line print a single integer — the answer to the problem.
Examples
Input
4
1 1
2 2
3 3
4 4
Output
4
Input
4
1 2
2 3
3 4
4 1
Output
0
Submitted Solution:
```
"""
Author: Sagar Pandey
"""
# ---------------------------------------------------Import Libraries---------------------------------------------------
import sys
import time
import os
from math import sqrt, log, log2, ceil, log10, gcd, floor, pow, sin, cos, tan, pi, inf, factorial
from copy import copy, deepcopy
from sys import exit, stdin, stdout
from collections import Counter, defaultdict, deque
from itertools import permutations
import heapq
from bisect import bisect_left as bl
# If the element is already present in the list,
# the left most position where element has to be inserted is returned.
from bisect import bisect_right as br
from bisect import bisect
# If the element is already present in the list,
# the right most position where element has to be inserted is r
# ---------------------------------------------------Global Variables---------------------------------------------------
# sys.setrecursionlimit(100000000)
mod = 1000000007
# ---------------------------------------------------Helper Functions---------------------------------------------------
iinp = lambda: int(sys.stdin.readline())
inp = lambda: sys.stdin.readline().strip()
strl = lambda: list(inp().strip().split(" "))
intl = lambda: list(map(int, inp().split(" ")))
mint = lambda: map(int, inp().split())
flol = lambda: list(map(float, inp().split(" ")))
flush = lambda: stdout.flush()
def permute(nums):
def fun(arr, nums, cur, v):
if len(cur) == len(nums):
arr.append(cur.copy())
i = 0
while i < len(nums):
if v[i]:
i += 1
continue
else:
cur.append(nums[i])
v[i] = 1
fun(arr, nums, cur, v)
cur.pop()
v[i] = 0
i += 1
# while i<len(nums) and nums[i]==nums[i-1]:i+=1 # Uncomment for unique permutations
return arr
res = []
nums.sort()
v = [0] * len(nums)
return fun(res, nums, [], v)
def subsets(res, index, arr, cur):
res.append(cur.copy())
for i in range(index, len(arr)):
cur.append(arr[i])
subsets(res, i + 1, arr, cur)
cur.pop()
return res
def sieve(N):
root = int(sqrt(N))
primes = [1] * (N + 1)
primes[0], primes[1] = 0, 0
for i in range(2, root + 1):
if primes[i]:
for j in range(i * i, N + 1, i):
primes[j] = 0
return primes
def bs(arr, l, r, x):
if x < arr[0] or x > arr[len(arr) - 1]:
return -1
while l <= r:
mid = l + (r - l) // 2
if arr[mid] == x:
return mid
elif arr[mid] < x:
l = mid + 1
else:
r = mid - 1
return -1
def isPrime(n):
if n <= 1: return False
if n <= 3: return True
if n % 2 == 0 or n % 3 == 0: return False
p = int(sqrt(n))
for i in range(5, p + 1, 6):
if n % i == 0 or n % (i + 2) == 0:
return False
return True
# -------------------------------------------------------Functions------------------------------------------------------
def solve():
n=iinp()
a=[]
for i in range(n):
a.append(intl())
ans=0
for i in range(n):
f=False
for j in range(n):
if i==j:
continue
else:
if a[i][0]==a[j][1]:
f=True
if f:
ans+=1
print(n-ans)
# -------------------------------------------------------Main Code------------------------------------------------------
start_time = time.time()
# for _ in range(iinp()):
solve()
# print("--- %s seconds ---" % (time.time() - start_time))
```
Yes
| 94,703 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Sereja and his friends went to a picnic. The guys had n soda bottles just for it. Sereja forgot the bottle opener as usual, so the guys had to come up with another way to open bottles.
Sereja knows that the i-th bottle is from brand ai, besides, you can use it to open other bottles of brand bi. You can use one bottle to open multiple other bottles. Sereja can open bottle with opened bottle or closed bottle.
Knowing this, Sereja wants to find out the number of bottles they've got that they won't be able to open in any way. Help him and find this number.
Input
The first line contains integer n (1 ≤ n ≤ 100) — the number of bottles. The next n lines contain the bottles' description. The i-th line contains two integers ai, bi (1 ≤ ai, bi ≤ 1000) — the description of the i-th bottle.
Output
In a single line print a single integer — the answer to the problem.
Examples
Input
4
1 1
2 2
3 3
4 4
Output
4
Input
4
1 2
2 3
3 4
4 1
Output
0
Submitted Solution:
```
n = int(input())
e = 0
a = []
b = [ [] for i in range(1001) ]
for i in range(n):
s,t = map(int,input().split())
a.append([i,s])
b[t].append(i)
for i in range(len(a)):
c1 = 0
for j in range(len(b[a[i][1]])):
if (b[a[i][1]][j] != i):
c1 = -1
if (c1 != -1):
e = e + 1
print(e)
```
Yes
| 94,704 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Sereja and his friends went to a picnic. The guys had n soda bottles just for it. Sereja forgot the bottle opener as usual, so the guys had to come up with another way to open bottles.
Sereja knows that the i-th bottle is from brand ai, besides, you can use it to open other bottles of brand bi. You can use one bottle to open multiple other bottles. Sereja can open bottle with opened bottle or closed bottle.
Knowing this, Sereja wants to find out the number of bottles they've got that they won't be able to open in any way. Help him and find this number.
Input
The first line contains integer n (1 ≤ n ≤ 100) — the number of bottles. The next n lines contain the bottles' description. The i-th line contains two integers ai, bi (1 ≤ ai, bi ≤ 1000) — the description of the i-th bottle.
Output
In a single line print a single integer — the answer to the problem.
Examples
Input
4
1 1
2 2
3 3
4 4
Output
4
Input
4
1 2
2 3
3 4
4 1
Output
0
Submitted Solution:
```
#Problem Set D: Collaborated with no one
n = int(input())
size = n+1
bottle_num = [0]*size
left_arr = []
right_arr = []
for i in range(n):
ab_list = list(map(int, input().split()))
if len(left_arr) == 0:
left_arr.append(0)
if len(right_arr) == 0:
right_arr.append(0)
left_arr.append(ab_list[0])
right_arr.append(ab_list[1])
for j in range(1,n+1):
for k in range(1,n+1):
if (j != k) and (left_arr[j] == right_arr[k]):
bottle_num[j] = 1
total = 0
for i in range(1,n+1):
total += bottle_num[i]
print(n-total)
```
Yes
| 94,705 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Sereja and his friends went to a picnic. The guys had n soda bottles just for it. Sereja forgot the bottle opener as usual, so the guys had to come up with another way to open bottles.
Sereja knows that the i-th bottle is from brand ai, besides, you can use it to open other bottles of brand bi. You can use one bottle to open multiple other bottles. Sereja can open bottle with opened bottle or closed bottle.
Knowing this, Sereja wants to find out the number of bottles they've got that they won't be able to open in any way. Help him and find this number.
Input
The first line contains integer n (1 ≤ n ≤ 100) — the number of bottles. The next n lines contain the bottles' description. The i-th line contains two integers ai, bi (1 ≤ ai, bi ≤ 1000) — the description of the i-th bottle.
Output
In a single line print a single integer — the answer to the problem.
Examples
Input
4
1 1
2 2
3 3
4 4
Output
4
Input
4
1 2
2 3
3 4
4 1
Output
0
Submitted Solution:
```
n = int(input())
a = [0] * n
b = [0] * n
ans = 0
for i in range(n):
a[i], b[i] = map(int, input().split())
for i in range(n):
for j in range(n):
if i != j and b[j] == a[i]:
break
else:
ans += 1
print(ans)
```
Yes
| 94,706 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Sereja and his friends went to a picnic. The guys had n soda bottles just for it. Sereja forgot the bottle opener as usual, so the guys had to come up with another way to open bottles.
Sereja knows that the i-th bottle is from brand ai, besides, you can use it to open other bottles of brand bi. You can use one bottle to open multiple other bottles. Sereja can open bottle with opened bottle or closed bottle.
Knowing this, Sereja wants to find out the number of bottles they've got that they won't be able to open in any way. Help him and find this number.
Input
The first line contains integer n (1 ≤ n ≤ 100) — the number of bottles. The next n lines contain the bottles' description. The i-th line contains two integers ai, bi (1 ≤ ai, bi ≤ 1000) — the description of the i-th bottle.
Output
In a single line print a single integer — the answer to the problem.
Examples
Input
4
1 1
2 2
3 3
4 4
Output
4
Input
4
1 2
2 3
3 4
4 1
Output
0
Submitted Solution:
```
n = int(input())
d = {}
for i in range(n):
a, b = map(int, input().split())
if a not in d:
d[a] = [1, 0]
else:
d[a][0] += 1
if b != a:
if not b in d:
d[b] = [1, 1]
elif d[b][1] == 0:
d[b][1] = 1
else:
d[b] = [1, 0]
ans = 0
for i in d:
if d[i][1] == 0:
ans += d[i][0]
print(ans)
```
No
| 94,707 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Sereja and his friends went to a picnic. The guys had n soda bottles just for it. Sereja forgot the bottle opener as usual, so the guys had to come up with another way to open bottles.
Sereja knows that the i-th bottle is from brand ai, besides, you can use it to open other bottles of brand bi. You can use one bottle to open multiple other bottles. Sereja can open bottle with opened bottle or closed bottle.
Knowing this, Sereja wants to find out the number of bottles they've got that they won't be able to open in any way. Help him and find this number.
Input
The first line contains integer n (1 ≤ n ≤ 100) — the number of bottles. The next n lines contain the bottles' description. The i-th line contains two integers ai, bi (1 ≤ ai, bi ≤ 1000) — the description of the i-th bottle.
Output
In a single line print a single integer — the answer to the problem.
Examples
Input
4
1 1
2 2
3 3
4 4
Output
4
Input
4
1 2
2 3
3 4
4 1
Output
0
Submitted Solution:
```
n = int(input())
al = []
bl = []
for i in range(n):
a, b = [int(x) for x in input().split()]
al.append(a)
if a != b:
bl.append(b)
else:
bl.append(-1)
count = 0
for bot in al:
if bot in bl:
count+=1
print(n-count)
```
No
| 94,708 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Sereja and his friends went to a picnic. The guys had n soda bottles just for it. Sereja forgot the bottle opener as usual, so the guys had to come up with another way to open bottles.
Sereja knows that the i-th bottle is from brand ai, besides, you can use it to open other bottles of brand bi. You can use one bottle to open multiple other bottles. Sereja can open bottle with opened bottle or closed bottle.
Knowing this, Sereja wants to find out the number of bottles they've got that they won't be able to open in any way. Help him and find this number.
Input
The first line contains integer n (1 ≤ n ≤ 100) — the number of bottles. The next n lines contain the bottles' description. The i-th line contains two integers ai, bi (1 ≤ ai, bi ≤ 1000) — the description of the i-th bottle.
Output
In a single line print a single integer — the answer to the problem.
Examples
Input
4
1 1
2 2
3 3
4 4
Output
4
Input
4
1 2
2 3
3 4
4 1
Output
0
Submitted Solution:
```
n = int(input())
matrix = []
count = 0
for _ in range(n):
l, r = map(int, input().split())
if l == r:
count += 1
print(count)
```
No
| 94,709 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Sereja and his friends went to a picnic. The guys had n soda bottles just for it. Sereja forgot the bottle opener as usual, so the guys had to come up with another way to open bottles.
Sereja knows that the i-th bottle is from brand ai, besides, you can use it to open other bottles of brand bi. You can use one bottle to open multiple other bottles. Sereja can open bottle with opened bottle or closed bottle.
Knowing this, Sereja wants to find out the number of bottles they've got that they won't be able to open in any way. Help him and find this number.
Input
The first line contains integer n (1 ≤ n ≤ 100) — the number of bottles. The next n lines contain the bottles' description. The i-th line contains two integers ai, bi (1 ≤ ai, bi ≤ 1000) — the description of the i-th bottle.
Output
In a single line print a single integer — the answer to the problem.
Examples
Input
4
1 1
2 2
3 3
4 4
Output
4
Input
4
1 2
2 3
3 4
4 1
Output
0
Submitted Solution:
```
n=int(input())
a=[]
b=[]
for x in range(0,n):
l=list(map(int,input().split(" ")))
a.append(l)
b.append(l[0])
c=0
for x,y in a:
if x==y:
c+=1
elif y in b:
pass
else:
c+=1
print(c)
```
No
| 94,710 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Manao is taking part in a quiz. The quiz consists of n consecutive questions. A correct answer gives one point to the player. The game also has a counter of consecutive correct answers. When the player answers a question correctly, the number on this counter increases by 1. If the player answers a question incorrectly, the counter is reset, that is, the number on it reduces to 0. If after an answer the counter reaches the number k, then it is reset, and the player's score is doubled. Note that in this case, first 1 point is added to the player's score, and then the total score is doubled. At the beginning of the game, both the player's score and the counter of consecutive correct answers are set to zero.
Manao remembers that he has answered exactly m questions correctly. But he does not remember the order in which the questions came. He's trying to figure out what his minimum score may be. Help him and compute the remainder of the corresponding number after division by 1000000009 (109 + 9).
Input
The single line contains three space-separated integers n, m and k (2 ≤ k ≤ n ≤ 109; 0 ≤ m ≤ n).
Output
Print a single integer — the remainder from division of Manao's minimum possible score in the quiz by 1000000009 (109 + 9).
Examples
Input
5 3 2
Output
3
Input
5 4 2
Output
6
Note
Sample 1. Manao answered 3 questions out of 5, and his score would double for each two consecutive correct answers. If Manao had answered the first, third and fifth questions, he would have scored as much as 3 points.
Sample 2. Now Manao answered 4 questions. The minimum possible score is obtained when the only wrong answer is to the question 4.
Also note that you are asked to minimize the score and not the remainder of the score modulo 1000000009. For example, if Manao could obtain either 2000000000 or 2000000020 points, the answer is 2000000000 mod 1000000009, even though 2000000020 mod 1000000009 is a smaller number.
Tags: binary search, greedy, math, matrices, number theory
Correct Solution:
```
n, m, k = map(int, input().split())
x, c, ic, ans, mod = min(m//(k-1), n-m), m, n-m, 0, 10**9 + 9
c = c - (k-1)*x
p, r = c//k, c%k
ans = ((((pow(2, p+1, mod) - 2 + mod)%mod) * (k%mod))%mod + (k-1)*x + r)%mod
print(ans)
```
| 94,711 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Manao is taking part in a quiz. The quiz consists of n consecutive questions. A correct answer gives one point to the player. The game also has a counter of consecutive correct answers. When the player answers a question correctly, the number on this counter increases by 1. If the player answers a question incorrectly, the counter is reset, that is, the number on it reduces to 0. If after an answer the counter reaches the number k, then it is reset, and the player's score is doubled. Note that in this case, first 1 point is added to the player's score, and then the total score is doubled. At the beginning of the game, both the player's score and the counter of consecutive correct answers are set to zero.
Manao remembers that he has answered exactly m questions correctly. But he does not remember the order in which the questions came. He's trying to figure out what his minimum score may be. Help him and compute the remainder of the corresponding number after division by 1000000009 (109 + 9).
Input
The single line contains three space-separated integers n, m and k (2 ≤ k ≤ n ≤ 109; 0 ≤ m ≤ n).
Output
Print a single integer — the remainder from division of Manao's minimum possible score in the quiz by 1000000009 (109 + 9).
Examples
Input
5 3 2
Output
3
Input
5 4 2
Output
6
Note
Sample 1. Manao answered 3 questions out of 5, and his score would double for each two consecutive correct answers. If Manao had answered the first, third and fifth questions, he would have scored as much as 3 points.
Sample 2. Now Manao answered 4 questions. The minimum possible score is obtained when the only wrong answer is to the question 4.
Also note that you are asked to minimize the score and not the remainder of the score modulo 1000000009. For example, if Manao could obtain either 2000000000 or 2000000020 points, the answer is 2000000000 mod 1000000009, even though 2000000020 mod 1000000009 is a smaller number.
Tags: binary search, greedy, math, matrices, number theory
Correct Solution:
```
z = 10**9+9
n,m,k = map(int,input().split())
i = n-m
x = (n-k+1)//k
if k*i>=n-k+1:
print((n-i)%z)
else:
l = n-k+1
f = l-(i-1)*k-1
t = f//k
f = t*k
v = 2*(pow(2,t,z)-1)*k+(n-f-i)
print(v%z)
```
| 94,712 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Manao is taking part in a quiz. The quiz consists of n consecutive questions. A correct answer gives one point to the player. The game also has a counter of consecutive correct answers. When the player answers a question correctly, the number on this counter increases by 1. If the player answers a question incorrectly, the counter is reset, that is, the number on it reduces to 0. If after an answer the counter reaches the number k, then it is reset, and the player's score is doubled. Note that in this case, first 1 point is added to the player's score, and then the total score is doubled. At the beginning of the game, both the player's score and the counter of consecutive correct answers are set to zero.
Manao remembers that he has answered exactly m questions correctly. But he does not remember the order in which the questions came. He's trying to figure out what his minimum score may be. Help him and compute the remainder of the corresponding number after division by 1000000009 (109 + 9).
Input
The single line contains three space-separated integers n, m and k (2 ≤ k ≤ n ≤ 109; 0 ≤ m ≤ n).
Output
Print a single integer — the remainder from division of Manao's minimum possible score in the quiz by 1000000009 (109 + 9).
Examples
Input
5 3 2
Output
3
Input
5 4 2
Output
6
Note
Sample 1. Manao answered 3 questions out of 5, and his score would double for each two consecutive correct answers. If Manao had answered the first, third and fifth questions, he would have scored as much as 3 points.
Sample 2. Now Manao answered 4 questions. The minimum possible score is obtained when the only wrong answer is to the question 4.
Also note that you are asked to minimize the score and not the remainder of the score modulo 1000000009. For example, if Manao could obtain either 2000000000 or 2000000020 points, the answer is 2000000000 mod 1000000009, even though 2000000020 mod 1000000009 is a smaller number.
Tags: binary search, greedy, math, matrices, number theory
Correct Solution:
```
n, corecte, k = map(int, input().split())
incorecte = n - corecte
mod = 10**9 + 9
corecte_consecutive = max(0, n - incorecte * k)
dublari = corecte_consecutive // k
corecte_ramase = corecte - corecte_consecutive
def power(b, exp):
if exp == 0: return 1
half = power(b, exp//2)
if exp%2 == 0: return (half*half) % mod
return (half*half*b) % mod
score = (power(2, dublari+1) - 2) * k + corecte_ramase + corecte_consecutive % k
print(score % mod)
```
| 94,713 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Manao is taking part in a quiz. The quiz consists of n consecutive questions. A correct answer gives one point to the player. The game also has a counter of consecutive correct answers. When the player answers a question correctly, the number on this counter increases by 1. If the player answers a question incorrectly, the counter is reset, that is, the number on it reduces to 0. If after an answer the counter reaches the number k, then it is reset, and the player's score is doubled. Note that in this case, first 1 point is added to the player's score, and then the total score is doubled. At the beginning of the game, both the player's score and the counter of consecutive correct answers are set to zero.
Manao remembers that he has answered exactly m questions correctly. But he does not remember the order in which the questions came. He's trying to figure out what his minimum score may be. Help him and compute the remainder of the corresponding number after division by 1000000009 (109 + 9).
Input
The single line contains three space-separated integers n, m and k (2 ≤ k ≤ n ≤ 109; 0 ≤ m ≤ n).
Output
Print a single integer — the remainder from division of Manao's minimum possible score in the quiz by 1000000009 (109 + 9).
Examples
Input
5 3 2
Output
3
Input
5 4 2
Output
6
Note
Sample 1. Manao answered 3 questions out of 5, and his score would double for each two consecutive correct answers. If Manao had answered the first, third and fifth questions, he would have scored as much as 3 points.
Sample 2. Now Manao answered 4 questions. The minimum possible score is obtained when the only wrong answer is to the question 4.
Also note that you are asked to minimize the score and not the remainder of the score modulo 1000000009. For example, if Manao could obtain either 2000000000 or 2000000020 points, the answer is 2000000000 mod 1000000009, even though 2000000020 mod 1000000009 is a smaller number.
Tags: binary search, greedy, math, matrices, number theory
Correct Solution:
```
n,m,k = map(int,input().split())
chunks = n//k
freespots = chunks*(k-1) + n%k
if m <= freespots:
print(m)
else:
doubles = m-freespots
dchunks = doubles
chunks -= dchunks
total = (pow(2,dchunks,1000000009)-1)*k*2
total += n%k + chunks*(k-1)
print(total%1000000009)
```
| 94,714 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Manao is taking part in a quiz. The quiz consists of n consecutive questions. A correct answer gives one point to the player. The game also has a counter of consecutive correct answers. When the player answers a question correctly, the number on this counter increases by 1. If the player answers a question incorrectly, the counter is reset, that is, the number on it reduces to 0. If after an answer the counter reaches the number k, then it is reset, and the player's score is doubled. Note that in this case, first 1 point is added to the player's score, and then the total score is doubled. At the beginning of the game, both the player's score and the counter of consecutive correct answers are set to zero.
Manao remembers that he has answered exactly m questions correctly. But he does not remember the order in which the questions came. He's trying to figure out what his minimum score may be. Help him and compute the remainder of the corresponding number after division by 1000000009 (109 + 9).
Input
The single line contains three space-separated integers n, m and k (2 ≤ k ≤ n ≤ 109; 0 ≤ m ≤ n).
Output
Print a single integer — the remainder from division of Manao's minimum possible score in the quiz by 1000000009 (109 + 9).
Examples
Input
5 3 2
Output
3
Input
5 4 2
Output
6
Note
Sample 1. Manao answered 3 questions out of 5, and his score would double for each two consecutive correct answers. If Manao had answered the first, third and fifth questions, he would have scored as much as 3 points.
Sample 2. Now Manao answered 4 questions. The minimum possible score is obtained when the only wrong answer is to the question 4.
Also note that you are asked to minimize the score and not the remainder of the score modulo 1000000009. For example, if Manao could obtain either 2000000000 or 2000000020 points, the answer is 2000000000 mod 1000000009, even though 2000000020 mod 1000000009 is a smaller number.
Tags: binary search, greedy, math, matrices, number theory
Correct Solution:
```
n,m,k=map(int,input().split())
mod=10**9+9
c=m
inc=n-m
rep=n//k
if rep<=inc:
print(c)
else:
rem_c=m-(k-1)*inc
score=(k-1)*inc
rep2=rem_c//k
score+=(pow(2,rep2+1,mod)-2)*k
rem_c-=rep2*k
score+=rem_c
print(score%mod)
```
| 94,715 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Manao is taking part in a quiz. The quiz consists of n consecutive questions. A correct answer gives one point to the player. The game also has a counter of consecutive correct answers. When the player answers a question correctly, the number on this counter increases by 1. If the player answers a question incorrectly, the counter is reset, that is, the number on it reduces to 0. If after an answer the counter reaches the number k, then it is reset, and the player's score is doubled. Note that in this case, first 1 point is added to the player's score, and then the total score is doubled. At the beginning of the game, both the player's score and the counter of consecutive correct answers are set to zero.
Manao remembers that he has answered exactly m questions correctly. But he does not remember the order in which the questions came. He's trying to figure out what his minimum score may be. Help him and compute the remainder of the corresponding number after division by 1000000009 (109 + 9).
Input
The single line contains three space-separated integers n, m and k (2 ≤ k ≤ n ≤ 109; 0 ≤ m ≤ n).
Output
Print a single integer — the remainder from division of Manao's minimum possible score in the quiz by 1000000009 (109 + 9).
Examples
Input
5 3 2
Output
3
Input
5 4 2
Output
6
Note
Sample 1. Manao answered 3 questions out of 5, and his score would double for each two consecutive correct answers. If Manao had answered the first, third and fifth questions, he would have scored as much as 3 points.
Sample 2. Now Manao answered 4 questions. The minimum possible score is obtained when the only wrong answer is to the question 4.
Also note that you are asked to minimize the score and not the remainder of the score modulo 1000000009. For example, if Manao could obtain either 2000000000 or 2000000020 points, the answer is 2000000000 mod 1000000009, even though 2000000020 mod 1000000009 is a smaller number.
Tags: binary search, greedy, math, matrices, number theory
Correct Solution:
```
b = 10**9 + 9
def f(q):
x = q//1000
y = q%1000
num = 2**1000 % b
res = 1
for i in range(x):
res = (res * num) % b
res = (res * 2**y) %b
return res
def F(n,m,k):
r = n%k
if m <= n//k * (k-1) + r :
print(m%b)
else:
q = m - (n//k * (k-1) + r)
print((m + (f(q+1)-q-2)*k)%b)
n,m,k = [int(x) for x in input().split(' ')]
F(n,m,k)
```
| 94,716 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Manao is taking part in a quiz. The quiz consists of n consecutive questions. A correct answer gives one point to the player. The game also has a counter of consecutive correct answers. When the player answers a question correctly, the number on this counter increases by 1. If the player answers a question incorrectly, the counter is reset, that is, the number on it reduces to 0. If after an answer the counter reaches the number k, then it is reset, and the player's score is doubled. Note that in this case, first 1 point is added to the player's score, and then the total score is doubled. At the beginning of the game, both the player's score and the counter of consecutive correct answers are set to zero.
Manao remembers that he has answered exactly m questions correctly. But he does not remember the order in which the questions came. He's trying to figure out what his minimum score may be. Help him and compute the remainder of the corresponding number after division by 1000000009 (109 + 9).
Input
The single line contains three space-separated integers n, m and k (2 ≤ k ≤ n ≤ 109; 0 ≤ m ≤ n).
Output
Print a single integer — the remainder from division of Manao's minimum possible score in the quiz by 1000000009 (109 + 9).
Examples
Input
5 3 2
Output
3
Input
5 4 2
Output
6
Note
Sample 1. Manao answered 3 questions out of 5, and his score would double for each two consecutive correct answers. If Manao had answered the first, third and fifth questions, he would have scored as much as 3 points.
Sample 2. Now Manao answered 4 questions. The minimum possible score is obtained when the only wrong answer is to the question 4.
Also note that you are asked to minimize the score and not the remainder of the score modulo 1000000009. For example, if Manao could obtain either 2000000000 or 2000000020 points, the answer is 2000000000 mod 1000000009, even though 2000000020 mod 1000000009 is a smaller number.
Tags: binary search, greedy, math, matrices, number theory
Correct Solution:
```
global MOD
MOD = int(1e9+9)
def pow(m, n):
ans = 1
while(n):
if n & 1:
ans = (ans*m) % MOD
m = (m*m) % MOD
n >>= 1
return ans
def quiz(n, m, k):
numk = n//k; # Divido mi problema en k pedazos
# Primer Problema
if numk*(k-1) >= m: # Si puedo efectuar al menos x * (k-1) respuestas correctas
return m; # retorno mi m que sera la cantidad de veces a cada k intentos que hago una respuesta correcta
rest_n = n-k*numk; # Analizo mi problema restante que seria n - k*numk(este es la cantidad de problemas q fueron analizados, es decir la cantidad de respuestas correctas que pude responder utilizando intentos a cada k intervalos)
rest_m = m-numk*(k-1); # analizo la cantidad de intentos que me quedan por efectuar, m - numk*(k-1), siendo num*(k-1) la cantidad de intentos realizados en el pedazo que se estaba analizando anteriormente, es decir m pedazos de tamanno k, donde se falla al menos 1 vez en cada caso para no llegar al valor de k
# Segundo Problema
if rest_m <= rest_n: # Si la cantidad de intentos que me queda es menor o igual que la cantidad de preguntas correctos que puedo hacer, entonces hago esta ultima pregunta correcta
return (numk*(k-1)+rest_m)%MOD; # y devuelvo la cantidad de puntos obtenidos en las numk*(k-1) veces q respondi bien y le sumo la cantidad de preguntas que me faltaban, tal que sumando estas preguntas no llego a k
# Tercer Problema
t = rest_m-rest_n; # Buscando diferencia de cantidad de aciertos restantes por efectuar con cantidad de aciertos restantes disponibles
num = rest_n+t*k; # Si a la cantidad de aciertos restantes disponibles restantes le sumamos la cantidad de aciertos que necesitamos que no se han podido efectuar hasta el momento multiplicada por k obtenemos
ans = (numk-t)*(k-1)%MOD; # Sumando a ans valores que no pertenecen a los k grupos(los que pertenecen a los k-1) (al hacer soluciones del final(grupo de tamanno menor q k) + soluciones que pertenecen a los k-1 grupos pero q la cantidad de respuestas correctas no es igual a k + grupos del comienzo los cuales la cantidad de aciertos es igual a k )
numk = num//k;
ans = (ans+num-numk*k)%MOD; # Sumando a ans valores que pertenecen a los k-1 grupos que no contienen k aciertos
return (m - numk*k + ((pow(2, numk+1) - 2) * k))%MOD
#ans = ans + 2*(k*(pow(2 , numk)-1))%MOD; # Sumando a ans valores que pertenecen a los k-1 grupos que contienen k aciertos, estos seran los puntos que se duplicaran
#return ans%MOD;
n, m, k = map(int, input().split())
print(quiz(n, m, k))
# linea 30
# A la cantidad de grupos de tamanno k que pueden formarse le restamos t, que seran la cantidad de grupos con al menos k-1 aciertos que se sumaran a la respuesta con unvalor de cantidad necesaria de estos grupos * k-1
# esto podra hacerse ya que al quedarnos t intentos que tenemos que efectuar correctamente, podemos asumir que los mismos se podran ubicar en los primeros x grupos de k respuestas correctas consecutivas , luego restamos la cantidad de respuestas que se exceden a la cantidad de grupos posibles de k intentos correctos y nos queda la cantidad de grupos que podrian tener k aciertos
# como nos interesan la cantidad de grupos que pueden tener k-1 aciertos multiplicamos esta resta anterior por k-1, obteniendo asi aquellos grupos que lenan exactamente k-1 aciertos correctamente
# este numero se lo sumamos a la cantidad total
```
| 94,717 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Manao is taking part in a quiz. The quiz consists of n consecutive questions. A correct answer gives one point to the player. The game also has a counter of consecutive correct answers. When the player answers a question correctly, the number on this counter increases by 1. If the player answers a question incorrectly, the counter is reset, that is, the number on it reduces to 0. If after an answer the counter reaches the number k, then it is reset, and the player's score is doubled. Note that in this case, first 1 point is added to the player's score, and then the total score is doubled. At the beginning of the game, both the player's score and the counter of consecutive correct answers are set to zero.
Manao remembers that he has answered exactly m questions correctly. But he does not remember the order in which the questions came. He's trying to figure out what his minimum score may be. Help him and compute the remainder of the corresponding number after division by 1000000009 (109 + 9).
Input
The single line contains three space-separated integers n, m and k (2 ≤ k ≤ n ≤ 109; 0 ≤ m ≤ n).
Output
Print a single integer — the remainder from division of Manao's minimum possible score in the quiz by 1000000009 (109 + 9).
Examples
Input
5 3 2
Output
3
Input
5 4 2
Output
6
Note
Sample 1. Manao answered 3 questions out of 5, and his score would double for each two consecutive correct answers. If Manao had answered the first, third and fifth questions, he would have scored as much as 3 points.
Sample 2. Now Manao answered 4 questions. The minimum possible score is obtained when the only wrong answer is to the question 4.
Also note that you are asked to minimize the score and not the remainder of the score modulo 1000000009. For example, if Manao could obtain either 2000000000 or 2000000020 points, the answer is 2000000000 mod 1000000009, even though 2000000020 mod 1000000009 is a smaller number.
Tags: binary search, greedy, math, matrices, number theory
Correct Solution:
```
global MOD
MOD = int(1e9+9)
def pow(m, n):
ans = 1
while(n):
if n & 1:
ans = (ans*m) % MOD
m = (m*m) % MOD
n >>= 1
return ans
def getAns(n, m, k):
numk = n//k; # Divido mi problema en k pedazos
# first judgment
if numk*(k-1) >= m: # Si puedo efectuar al menos x * (k-1) respuestas correctas
return m; # retorno mi m que sera la cantidad de veces a cada k intentos que hago una respuesta correcta
rest_n = n-k*numk; # Analizo mi problema restante que seria n - k*numk(este es la cantidad de problemas q fueron analizados, es decir la cantidad de respuestas correctas que pude responder utilizando intentos a cada k intervalos)
rest_m = m-numk*(k-1); # analizo la cantidad de intentos que me quedan por efectuar, m - numk*(k-1), siendo num*(k-1) la cantidad de intentos realizados en el pedazo que se estaba analizando anteriormente, es decir m pedazos de tamanno k, donde se falla al menos 1 vez en cada caso para no llegar al valor de k
# second judgment
if rest_m <= rest_n: # Si la cantidad de intentos que me queda es menor o igual que la cantidad de preguntas correctos que puedo hacer, entonces hago esta ultima pregunta correcta
return (numk*(k-1)+rest_m)%MOD; # y devuelvo la cantidad de puntos obtenidos en las numk*(k-1) veces q respondi bien y le sumo la cantidad de preguntas que me faltaban, tal que sumando estas preguntas no llego a k
# Third judgment
t = rest_m-rest_n;
num = rest_n+t*k;
ans = (numk-t)*(k-1)%MOD;
numk = num//k;
ans = (ans+num-numk*k)%MOD;
ans = ans + 2*(k*(pow(2 , numk)-1))%MOD;
return ans%MOD;
n, m, k = map(int, input().split())
print(getAns(n, m, k))
```
| 94,718 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Manao is taking part in a quiz. The quiz consists of n consecutive questions. A correct answer gives one point to the player. The game also has a counter of consecutive correct answers. When the player answers a question correctly, the number on this counter increases by 1. If the player answers a question incorrectly, the counter is reset, that is, the number on it reduces to 0. If after an answer the counter reaches the number k, then it is reset, and the player's score is doubled. Note that in this case, first 1 point is added to the player's score, and then the total score is doubled. At the beginning of the game, both the player's score and the counter of consecutive correct answers are set to zero.
Manao remembers that he has answered exactly m questions correctly. But he does not remember the order in which the questions came. He's trying to figure out what his minimum score may be. Help him and compute the remainder of the corresponding number after division by 1000000009 (109 + 9).
Input
The single line contains three space-separated integers n, m and k (2 ≤ k ≤ n ≤ 109; 0 ≤ m ≤ n).
Output
Print a single integer — the remainder from division of Manao's minimum possible score in the quiz by 1000000009 (109 + 9).
Examples
Input
5 3 2
Output
3
Input
5 4 2
Output
6
Note
Sample 1. Manao answered 3 questions out of 5, and his score would double for each two consecutive correct answers. If Manao had answered the first, third and fifth questions, he would have scored as much as 3 points.
Sample 2. Now Manao answered 4 questions. The minimum possible score is obtained when the only wrong answer is to the question 4.
Also note that you are asked to minimize the score and not the remainder of the score modulo 1000000009. For example, if Manao could obtain either 2000000000 or 2000000020 points, the answer is 2000000000 mod 1000000009, even though 2000000020 mod 1000000009 is a smaller number.
Submitted Solution:
```
from __future__ import division, print_function
import os
import sys
from io import BytesIO, IOBase
def main():
n, m, k = [ int(x) for x in input().split() ]
mod = 1000000009
availablePositions = (k - 1) * (n // k) + n % k
if availablePositions >= m:
points = m
else:
positionsLeft = m - availablePositions
points = (
((pow(2, positionsLeft + 1, mod) - 2) * k) % mod
+ (m - k * positionsLeft) % mod
) % mod
print(points)
BUFFSIZE = 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, BUFFSIZE))
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, BUFFSIZE))
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")
input = lambda: sys.stdin.readline().rstrip("\r\n")
def print(*args, **kwargs):
sep = kwargs.pop("sep", " ")
file = kwargs.pop("file", sys.stdout)
atStart = True
for x in args:
if not atStart:
file.write(sep)
file.write(str(x))
atStart = False
file.write(kwargs.pop("end", "\n"))
if kwargs.pop("flush", False):
file.flush()
sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout)
main()
```
Yes
| 94,719 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Manao is taking part in a quiz. The quiz consists of n consecutive questions. A correct answer gives one point to the player. The game also has a counter of consecutive correct answers. When the player answers a question correctly, the number on this counter increases by 1. If the player answers a question incorrectly, the counter is reset, that is, the number on it reduces to 0. If after an answer the counter reaches the number k, then it is reset, and the player's score is doubled. Note that in this case, first 1 point is added to the player's score, and then the total score is doubled. At the beginning of the game, both the player's score and the counter of consecutive correct answers are set to zero.
Manao remembers that he has answered exactly m questions correctly. But he does not remember the order in which the questions came. He's trying to figure out what his minimum score may be. Help him and compute the remainder of the corresponding number after division by 1000000009 (109 + 9).
Input
The single line contains three space-separated integers n, m and k (2 ≤ k ≤ n ≤ 109; 0 ≤ m ≤ n).
Output
Print a single integer — the remainder from division of Manao's minimum possible score in the quiz by 1000000009 (109 + 9).
Examples
Input
5 3 2
Output
3
Input
5 4 2
Output
6
Note
Sample 1. Manao answered 3 questions out of 5, and his score would double for each two consecutive correct answers. If Manao had answered the first, third and fifth questions, he would have scored as much as 3 points.
Sample 2. Now Manao answered 4 questions. The minimum possible score is obtained when the only wrong answer is to the question 4.
Also note that you are asked to minimize the score and not the remainder of the score modulo 1000000009. For example, if Manao could obtain either 2000000000 or 2000000020 points, the answer is 2000000000 mod 1000000009, even though 2000000020 mod 1000000009 is a smaller number.
Submitted Solution:
```
###### ### ####### ####### ## # ##### ### #####
# # # # # # # # # # # # # ###
# # # # # # # # # # # # # ###
###### ######### # # # # # # ######### #
###### ######### # # # # # # ######### #
# # # # # # # # # # #### # # #
# # # # # # # ## # # # # #
###### # # ####### ####### # # ##### # # # #
# mandatory imports
import os
import sys
from io import BytesIO, IOBase
from math import log2, ceil, sqrt, gcd, log
# optional imports
# from itertools import permutations
# from functools import cmp_to_key # for adding custom comparator
# from fractions import Fraction
from collections import *
from bisect import *
# from __future__ import print_function # for PyPy2
# from heapq import *
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")
g = lambda : input().strip()
gl = lambda : g().split()
gil = lambda : [int(var) for var in gl()]
gfl = lambda : [float(var) for var in gl()]
gcl = lambda : list(g())
gbs = lambda : [int(var) for var in g()]
rr = lambda x : reversed(range(x))
mod = int(1e9)+7
inf = float("inf")
mod = int(1e9 + 9)
n, m, k = gil()
ans = min(n%k, m)%mod
m -= min(m, n%k)
n -= n%k
if m:
l = n//k
dbl = max(0, m - (l*(k-1)))
if dbl :
delta = (pow(2, dbl+1, mod) + mod - 2)%mod
delta *= k
delta %= mod
ans += delta
ans %= mod
l -= dbl
ans += (m - dbl*k)%mod
print(ans%mod)
```
Yes
| 94,720 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Manao is taking part in a quiz. The quiz consists of n consecutive questions. A correct answer gives one point to the player. The game also has a counter of consecutive correct answers. When the player answers a question correctly, the number on this counter increases by 1. If the player answers a question incorrectly, the counter is reset, that is, the number on it reduces to 0. If after an answer the counter reaches the number k, then it is reset, and the player's score is doubled. Note that in this case, first 1 point is added to the player's score, and then the total score is doubled. At the beginning of the game, both the player's score and the counter of consecutive correct answers are set to zero.
Manao remembers that he has answered exactly m questions correctly. But he does not remember the order in which the questions came. He's trying to figure out what his minimum score may be. Help him and compute the remainder of the corresponding number after division by 1000000009 (109 + 9).
Input
The single line contains three space-separated integers n, m and k (2 ≤ k ≤ n ≤ 109; 0 ≤ m ≤ n).
Output
Print a single integer — the remainder from division of Manao's minimum possible score in the quiz by 1000000009 (109 + 9).
Examples
Input
5 3 2
Output
3
Input
5 4 2
Output
6
Note
Sample 1. Manao answered 3 questions out of 5, and his score would double for each two consecutive correct answers. If Manao had answered the first, third and fifth questions, he would have scored as much as 3 points.
Sample 2. Now Manao answered 4 questions. The minimum possible score is obtained when the only wrong answer is to the question 4.
Also note that you are asked to minimize the score and not the remainder of the score modulo 1000000009. For example, if Manao could obtain either 2000000000 or 2000000020 points, the answer is 2000000000 mod 1000000009, even though 2000000020 mod 1000000009 is a smaller number.
Submitted Solution:
```
n, m, k = map(int, input().split())
if (n - m) >= n//k:
print (m)
else:
longest_correct_streak = n - k*(n - m)
p = longest_correct_streak//k
print ((k*(pow(2, p+1, 1000000009) - 2) + (longest_correct_streak % k) + (n - m)*(k - 1)) % 1000000009)
```
Yes
| 94,721 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Manao is taking part in a quiz. The quiz consists of n consecutive questions. A correct answer gives one point to the player. The game also has a counter of consecutive correct answers. When the player answers a question correctly, the number on this counter increases by 1. If the player answers a question incorrectly, the counter is reset, that is, the number on it reduces to 0. If after an answer the counter reaches the number k, then it is reset, and the player's score is doubled. Note that in this case, first 1 point is added to the player's score, and then the total score is doubled. At the beginning of the game, both the player's score and the counter of consecutive correct answers are set to zero.
Manao remembers that he has answered exactly m questions correctly. But he does not remember the order in which the questions came. He's trying to figure out what his minimum score may be. Help him and compute the remainder of the corresponding number after division by 1000000009 (109 + 9).
Input
The single line contains three space-separated integers n, m and k (2 ≤ k ≤ n ≤ 109; 0 ≤ m ≤ n).
Output
Print a single integer — the remainder from division of Manao's minimum possible score in the quiz by 1000000009 (109 + 9).
Examples
Input
5 3 2
Output
3
Input
5 4 2
Output
6
Note
Sample 1. Manao answered 3 questions out of 5, and his score would double for each two consecutive correct answers. If Manao had answered the first, third and fifth questions, he would have scored as much as 3 points.
Sample 2. Now Manao answered 4 questions. The minimum possible score is obtained when the only wrong answer is to the question 4.
Also note that you are asked to minimize the score and not the remainder of the score modulo 1000000009. For example, if Manao could obtain either 2000000000 or 2000000020 points, the answer is 2000000000 mod 1000000009, even though 2000000020 mod 1000000009 is a smaller number.
Submitted Solution:
```
import sys
from math import *
def minp():
return sys.stdin.readline().strip()
def mint():
return int(minp())
def mints():
return map(int, minp().split())
def add(a,b):
return (a+b)%1000000009
def sub(a,b):
return (a-(b%1000000009)+1000000009)%1000000009
def mul(a,b):
return (a*b)%1000000009
def qpow(a,n):
k = a
r = 1
for i in range(32):
if n & (1<<i):
r = mul(r,k)
k = mul(k,k)
return r
n, m, k = mints()
c = (n+1)//k
z = c*(k-1)
if n-c*k >= 0:
z += n-c*k
d = 0
if z < m:
d = m-z
else:
print(m)
exit(0)
s = mul(k,mul(2, sub(qpow(2, d), 1)))
#print(c,d,z,s)
s = sub(add(s, z),mul(d,(k-1)))
print(s)
```
Yes
| 94,722 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Manao is taking part in a quiz. The quiz consists of n consecutive questions. A correct answer gives one point to the player. The game also has a counter of consecutive correct answers. When the player answers a question correctly, the number on this counter increases by 1. If the player answers a question incorrectly, the counter is reset, that is, the number on it reduces to 0. If after an answer the counter reaches the number k, then it is reset, and the player's score is doubled. Note that in this case, first 1 point is added to the player's score, and then the total score is doubled. At the beginning of the game, both the player's score and the counter of consecutive correct answers are set to zero.
Manao remembers that he has answered exactly m questions correctly. But he does not remember the order in which the questions came. He's trying to figure out what his minimum score may be. Help him and compute the remainder of the corresponding number after division by 1000000009 (109 + 9).
Input
The single line contains three space-separated integers n, m and k (2 ≤ k ≤ n ≤ 109; 0 ≤ m ≤ n).
Output
Print a single integer — the remainder from division of Manao's minimum possible score in the quiz by 1000000009 (109 + 9).
Examples
Input
5 3 2
Output
3
Input
5 4 2
Output
6
Note
Sample 1. Manao answered 3 questions out of 5, and his score would double for each two consecutive correct answers. If Manao had answered the first, third and fifth questions, he would have scored as much as 3 points.
Sample 2. Now Manao answered 4 questions. The minimum possible score is obtained when the only wrong answer is to the question 4.
Also note that you are asked to minimize the score and not the remainder of the score modulo 1000000009. For example, if Manao could obtain either 2000000000 or 2000000020 points, the answer is 2000000000 mod 1000000009, even though 2000000020 mod 1000000009 is a smaller number.
Submitted Solution:
```
n, corecte, k = map(int, input().split())
incorecte = n - corecte
mod = 10**9 + 9
corecte_consecutive = max(0, n - incorecte * k)
dublari = corecte_consecutive // k
corecte_ramase = corecte - corecte_consecutive
#print("dublari = %i" % dublari)
score = 0
#for i in range(0, dublari):
# score += k
# score *= 2
# score %= mod
def power(b, exp):
if exp == 0: return 1
half = power(b, exp//2)
if exp % 2 == 0: return (half*half)
else: return (half*half*b)
score = power(2, dublari) + 1
score = ~score
score *= k
#print("scor chiar dupa dublari = %i" % score)
#print("corecte_consecutive = %i" % corecte_consecutive)
#print("dublari = %i" % dublari)
#print("corecte_ramase = %i" % corecte_ramase)
score += corecte_ramase
score += corecte_consecutive % k
score = -score
print(score % mod)
"""
sirul trebuie structurat asa:
RRRRRRRRRRRR WRRRRR WRRRRR WRRRRR WRRRRR
"""
```
No
| 94,723 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Manao is taking part in a quiz. The quiz consists of n consecutive questions. A correct answer gives one point to the player. The game also has a counter of consecutive correct answers. When the player answers a question correctly, the number on this counter increases by 1. If the player answers a question incorrectly, the counter is reset, that is, the number on it reduces to 0. If after an answer the counter reaches the number k, then it is reset, and the player's score is doubled. Note that in this case, first 1 point is added to the player's score, and then the total score is doubled. At the beginning of the game, both the player's score and the counter of consecutive correct answers are set to zero.
Manao remembers that he has answered exactly m questions correctly. But he does not remember the order in which the questions came. He's trying to figure out what his minimum score may be. Help him and compute the remainder of the corresponding number after division by 1000000009 (109 + 9).
Input
The single line contains three space-separated integers n, m and k (2 ≤ k ≤ n ≤ 109; 0 ≤ m ≤ n).
Output
Print a single integer — the remainder from division of Manao's minimum possible score in the quiz by 1000000009 (109 + 9).
Examples
Input
5 3 2
Output
3
Input
5 4 2
Output
6
Note
Sample 1. Manao answered 3 questions out of 5, and his score would double for each two consecutive correct answers. If Manao had answered the first, third and fifth questions, he would have scored as much as 3 points.
Sample 2. Now Manao answered 4 questions. The minimum possible score is obtained when the only wrong answer is to the question 4.
Also note that you are asked to minimize the score and not the remainder of the score modulo 1000000009. For example, if Manao could obtain either 2000000000 or 2000000020 points, the answer is 2000000000 mod 1000000009, even though 2000000020 mod 1000000009 is a smaller number.
Submitted Solution:
```
def game(n,m,k):
dp=[0]*(n)
for i in range(0,n,2):
dp[i]=1
while dp.count(1)<m:
for i in range(len(dp)):
if dp[i]==0:
dp[i]=1
if dp.count(i)==m:
break
score=0
curr=0
for i in dp:
if i==1:
curr+=1
score+=1
if curr==k:
score*=2
curr=0
if i==0:
curr=0
return score%(10**9+9)
a,b,c=map(int,input().strip().split())
print(game(a,b,c))
```
No
| 94,724 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Manao is taking part in a quiz. The quiz consists of n consecutive questions. A correct answer gives one point to the player. The game also has a counter of consecutive correct answers. When the player answers a question correctly, the number on this counter increases by 1. If the player answers a question incorrectly, the counter is reset, that is, the number on it reduces to 0. If after an answer the counter reaches the number k, then it is reset, and the player's score is doubled. Note that in this case, first 1 point is added to the player's score, and then the total score is doubled. At the beginning of the game, both the player's score and the counter of consecutive correct answers are set to zero.
Manao remembers that he has answered exactly m questions correctly. But he does not remember the order in which the questions came. He's trying to figure out what his minimum score may be. Help him and compute the remainder of the corresponding number after division by 1000000009 (109 + 9).
Input
The single line contains three space-separated integers n, m and k (2 ≤ k ≤ n ≤ 109; 0 ≤ m ≤ n).
Output
Print a single integer — the remainder from division of Manao's minimum possible score in the quiz by 1000000009 (109 + 9).
Examples
Input
5 3 2
Output
3
Input
5 4 2
Output
6
Note
Sample 1. Manao answered 3 questions out of 5, and his score would double for each two consecutive correct answers. If Manao had answered the first, third and fifth questions, he would have scored as much as 3 points.
Sample 2. Now Manao answered 4 questions. The minimum possible score is obtained when the only wrong answer is to the question 4.
Also note that you are asked to minimize the score and not the remainder of the score modulo 1000000009. For example, if Manao could obtain either 2000000000 or 2000000020 points, the answer is 2000000000 mod 1000000009, even though 2000000020 mod 1000000009 is a smaller number.
Submitted Solution:
```
from sys import stdin
mod = 1000000009
def find(k, ak):
return ((((4*pow(2, ak, mod))%mod - (4 + 2*ak)%mod + mod)%mod)*k)%mod
n, m, k = map(int, stdin.readline().split())
w = min(n//k, n-m)
ak = n//k - w
print((find(k, ak) + m - k*ak)%mod)
```
No
| 94,725 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Manao is taking part in a quiz. The quiz consists of n consecutive questions. A correct answer gives one point to the player. The game also has a counter of consecutive correct answers. When the player answers a question correctly, the number on this counter increases by 1. If the player answers a question incorrectly, the counter is reset, that is, the number on it reduces to 0. If after an answer the counter reaches the number k, then it is reset, and the player's score is doubled. Note that in this case, first 1 point is added to the player's score, and then the total score is doubled. At the beginning of the game, both the player's score and the counter of consecutive correct answers are set to zero.
Manao remembers that he has answered exactly m questions correctly. But he does not remember the order in which the questions came. He's trying to figure out what his minimum score may be. Help him and compute the remainder of the corresponding number after division by 1000000009 (109 + 9).
Input
The single line contains three space-separated integers n, m and k (2 ≤ k ≤ n ≤ 109; 0 ≤ m ≤ n).
Output
Print a single integer — the remainder from division of Manao's minimum possible score in the quiz by 1000000009 (109 + 9).
Examples
Input
5 3 2
Output
3
Input
5 4 2
Output
6
Note
Sample 1. Manao answered 3 questions out of 5, and his score would double for each two consecutive correct answers. If Manao had answered the first, third and fifth questions, he would have scored as much as 3 points.
Sample 2. Now Manao answered 4 questions. The minimum possible score is obtained when the only wrong answer is to the question 4.
Also note that you are asked to minimize the score and not the remainder of the score modulo 1000000009. For example, if Manao could obtain either 2000000000 or 2000000020 points, the answer is 2000000000 mod 1000000009, even though 2000000020 mod 1000000009 is a smaller number.
Submitted Solution:
```
z = 10**9+9
n,m,k = map(int,input().split())
i = n-m
x = (n-k+1)//k
if i>=x:
print((n-i)%z)
else:
l = n-k+1
f = l-(i-1)*k-1
t = f//k
f = t*k
v = 2*(pow(2,t,z)-1)*k+(n-f-i)
print(v%z)
```
No
| 94,726 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
No Great Victory anniversary in Berland has ever passed without the war parade. This year is not an exception. That’s why the preparations are on in full strength. Tanks are building a line, artillery mounts are ready to fire, soldiers are marching on the main square... And the air forces general Mr. Generalov is in trouble again. This year a lot of sky-scrapers have been built which makes it difficult for the airplanes to fly above the city. It was decided that the planes should fly strictly from south to north. Moreover, there must be no sky scraper on a plane’s route, otherwise the anniversary will become a tragedy. The Ministry of Building gave the data on n sky scrapers (the rest of the buildings are rather small and will not be a problem to the planes). When looking at the city from south to north as a geometrical plane, the i-th building is a rectangle of height hi. Its westernmost point has the x-coordinate of li and the easternmost — of ri. The terrain of the area is plain so that all the buildings stand on one level. Your task as the Ministry of Defence’s head programmer is to find an enveloping polyline using the data on the sky-scrapers. The polyline’s properties are as follows:
* If you look at the city from south to north as a plane, then any part of any building will be inside or on the boarder of the area that the polyline encloses together with the land surface.
* The polyline starts and ends on the land level, i.e. at the height equal to 0.
* The segments of the polyline are parallel to the coordinate axes, i.e. they can only be vertical or horizontal.
* The polyline’s vertices should have integer coordinates.
* If you look at the city from south to north the polyline (together with the land surface) must enclose the minimum possible area.
* The polyline must have the smallest length among all the polylines, enclosing the minimum possible area with the land.
* The consecutive segments of the polyline must be perpendicular.
<image> Picture to the second sample test (the enveloping polyline is marked on the right).
Input
The first input line contains integer n (1 ≤ n ≤ 100000). Then follow n lines, each containing three integers hi, li, ri (1 ≤ hi ≤ 109, - 109 ≤ li < ri ≤ 109).
Output
In the first line output integer m — amount of vertices of the enveloping polyline. The next m lines should contain 2 integers each — the position and the height of the polyline’s vertex. Output the coordinates of each vertex in the order of traversing the polyline from west to east. Remember that the first and the last vertices of the polyline should have the height of 0.
Examples
Input
2
3 0 2
4 1 3
Output
6
0 0
0 3
1 3
1 4
3 4
3 0
Input
5
3 -3 0
2 -1 1
4 2 4
2 3 7
3 6 8
Output
14
-3 0
-3 3
0 3
0 2
1 2
1 0
2 0
2 4
4 4
4 2
6 2
6 3
8 3
8 0
Submitted Solution:
```
import sys
from array import array # noqa: F401
from collections import defaultdict
from heapq import heappop, heappush
def input():
with open('input.txt') as fp:
return fp.readlines()
def output(ans: str):
with open('output.txt', mode='w') as fp:
fp.write(ans)
'''
def input():
return [line.decode('utf-8') for line in sys.stdin.buffer.readlines()]
def output(ans):
print(ans)
'''
s = input()
n = int(s[0])
dd = defaultdict(list)
pos_set = set()
pos_a, hi_a = [0] * n, [0] * n
for i, (h, l, r) in enumerate(map(int, line.split()) for line in s[1:]):
hi_a[i] = -h
pos_a[i] = r
dd[l].append(i)
pos_set.add(l)
pos_set.add(r)
hi_pos = defaultdict(int)
hi_pos[0] = 10**9 + 100
hq = [0]
ans = []
hi = 0
for pos in sorted(pos_set):
while hq and hi_pos[hq[0]] <= pos:
heappop(hq)
if pos in dd:
for i in dd[pos]:
heappush(hq, hi_a[i])
hi_pos[hi_a[i]] = max(hi_pos[hi_a[i]], pos_a[i])
if hi != hq[0]:
ans.append(f'{pos} {-hi}')
ans.append(f'{pos} {-hq[0]}')
hi = hq[0]
output(str(len(ans)) + '\n' + '\n'.join(ans))
```
No
| 94,727 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
No Great Victory anniversary in Berland has ever passed without the war parade. This year is not an exception. That’s why the preparations are on in full strength. Tanks are building a line, artillery mounts are ready to fire, soldiers are marching on the main square... And the air forces general Mr. Generalov is in trouble again. This year a lot of sky-scrapers have been built which makes it difficult for the airplanes to fly above the city. It was decided that the planes should fly strictly from south to north. Moreover, there must be no sky scraper on a plane’s route, otherwise the anniversary will become a tragedy. The Ministry of Building gave the data on n sky scrapers (the rest of the buildings are rather small and will not be a problem to the planes). When looking at the city from south to north as a geometrical plane, the i-th building is a rectangle of height hi. Its westernmost point has the x-coordinate of li and the easternmost — of ri. The terrain of the area is plain so that all the buildings stand on one level. Your task as the Ministry of Defence’s head programmer is to find an enveloping polyline using the data on the sky-scrapers. The polyline’s properties are as follows:
* If you look at the city from south to north as a plane, then any part of any building will be inside or on the boarder of the area that the polyline encloses together with the land surface.
* The polyline starts and ends on the land level, i.e. at the height equal to 0.
* The segments of the polyline are parallel to the coordinate axes, i.e. they can only be vertical or horizontal.
* The polyline’s vertices should have integer coordinates.
* If you look at the city from south to north the polyline (together with the land surface) must enclose the minimum possible area.
* The polyline must have the smallest length among all the polylines, enclosing the minimum possible area with the land.
* The consecutive segments of the polyline must be perpendicular.
<image> Picture to the second sample test (the enveloping polyline is marked on the right).
Input
The first input line contains integer n (1 ≤ n ≤ 100000). Then follow n lines, each containing three integers hi, li, ri (1 ≤ hi ≤ 109, - 109 ≤ li < ri ≤ 109).
Output
In the first line output integer m — amount of vertices of the enveloping polyline. The next m lines should contain 2 integers each — the position and the height of the polyline’s vertex. Output the coordinates of each vertex in the order of traversing the polyline from west to east. Remember that the first and the last vertices of the polyline should have the height of 0.
Examples
Input
2
3 0 2
4 1 3
Output
6
0 0
0 3
1 3
1 4
3 4
3 0
Input
5
3 -3 0
2 -1 1
4 2 4
2 3 7
3 6 8
Output
14
-3 0
-3 3
0 3
0 2
1 2
1 0
2 0
2 4
4 4
4 2
6 2
6 3
8 3
8 0
Submitted Solution:
```
import sys
from array import array # noqa: F401
from collections import defaultdict
from heapq import heappop, heappush
def input():
with open('input.txt') as fp:
return fp.readlines()
def output(ans: str):
with open('output.txt', mode='w') as fp:
fp.write(ans)
'''
def input():
return [line.decode('utf-8') for line in sys.stdin.buffer.readlines()]
def output(ans):
print(ans)
'''
s = input()
n = int(s[0])
dd = defaultdict(list)
pos_set = set()
pos_a, hi_a = [0] * n, [0] * n
for i, (h, l, r) in enumerate(map(int, line.split()) for line in s[1:]):
hi_a[i] = -h
pos_a[i] = r
dd[l].append(i)
pos_set.add(l)
pos_set.add(r)
hi_pos = defaultdict(lambda: -10**9 - 100)
hi_pos[0] = 10**9 + 100
hq = [0]
ans = []
hi = 0
for pos in sorted(pos_set):
while hq and hi_pos[hq[0]] <= pos:
heappop(hq)
if pos in dd:
for i in dd[pos]:
heappush(hq, hi_a[i])
hi_pos[hi_a[i]] = max(hi_pos[hi_a[i]], pos_a[i])
if hi != hq[0]:
ans.append(f'{pos} {-hi}\n{pos} {-hq[0]}')
hi = hq[0]
output(str(len(ans)) + '\n' + '\n'.join(ans))
```
No
| 94,728 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Iahub likes trees very much. Recently he discovered an interesting tree named propagating tree. The tree consists of n nodes numbered from 1 to n, each node i having an initial value ai. The root of the tree is node 1.
This tree has a special property: when a value val is added to a value of node i, the value -val is added to values of all the children of node i. Note that when you add value -val to a child of node i, you also add -(-val) to all children of the child of node i and so on. Look an example explanation to understand better how it works.
This tree supports two types of queries:
* "1 x val" — val is added to the value of node x;
* "2 x" — print the current value of node x.
In order to help Iahub understand the tree better, you must answer m queries of the preceding type.
Input
The first line contains two integers n and m (1 ≤ n, m ≤ 200000). The second line contains n integers a1, a2, ..., an (1 ≤ ai ≤ 1000). Each of the next n–1 lines contains two integers vi and ui (1 ≤ vi, ui ≤ n), meaning that there is an edge between nodes vi and ui.
Each of the next m lines contains a query in the format described above. It is guaranteed that the following constraints hold for all queries: 1 ≤ x ≤ n, 1 ≤ val ≤ 1000.
Output
For each query of type two (print the value of node x) you must print the answer to the query on a separate line. The queries must be answered in the order given in the input.
Examples
Input
5 5
1 2 1 1 2
1 2
1 3
2 4
2 5
1 2 3
1 1 2
2 1
2 2
2 4
Output
3
3
0
Note
The values of the nodes are [1, 2, 1, 1, 2] at the beginning.
Then value 3 is added to node 2. It propagates and value -3 is added to it's sons, node 4 and node 5. Then it cannot propagate any more. So the values of the nodes are [1, 5, 1, - 2, - 1].
Then value 2 is added to node 1. It propagates and value -2 is added to it's sons, node 2 and node 3. From node 2 it propagates again, adding value 2 to it's sons, node 4 and node 5. Node 3 has no sons, so it cannot propagate from there. The values of the nodes are [3, 3, - 1, 0, 1].
You can see all the definitions about the tree at the following link: http://en.wikipedia.org/wiki/Tree_(graph_theory)
Tags: data structures, dfs and similar, trees
Correct Solution:
```
class BIT():
"""区間加算、一点取得クエリをそれぞれO(logN)で応えるデータ構造を構築する
add: 区間[begin, end)にvalを加える
get_val: i番目(0-indexed)の値を求める
"""
def __init__(self, n):
self.n = n
self.bit = [0] * (n + 1)
def get_val(self, i):
i = i + 1
s = 0
while i <= self.n:
s += self.bit[i]
i += i & -i
return s
def _add(self, i, val):
while i > 0:
self.bit[i] += val
i -= i & -i
def add(self, i, j, val):
self._add(j, val)
self._add(i, -val)
from collections import deque
import sys
input = sys.stdin.readline
def eular_tour(tree: list, root: int):
"""頂点に対するオイラーツアーを行う
posの部分木に区間[begin[pos], end[pos])が対応する
"""
n = len(tree)
res = []
begin = [-1] * n
end = [-1] * n
visited = [False] * n
visited[root] = True
q = deque([root])
while q:
pos = q.pop()
res.append(pos)
end[pos] = len(res)
if begin[pos] == -1:
begin[pos] = len(res) - 1
for next_pos in tree[pos]:
if visited[next_pos]:
continue
else:
visited[next_pos] = True
q.append(pos)
q.append(next_pos)
return res, begin, end
n, q = map(int, input().split())
init_cost = list(map(int, input().split()))
info = [list(map(int, input().split())) for i in range(n-1)]
query = [list(map(int, input().split())) for i in range(q)]
tree = [[] for i in range(n)]
for i in range(n-1):
a, b = info[i]
a -= 1
b -= 1
tree[a].append(b)
tree[b].append(a)
res, begin, end = eular_tour(tree, 0)
even_res = []
odd_res = []
for i in range(len(res)):
if i % 2 == 0:
even_res.append(res[i])
else:
odd_res.append(res[i])
even_bit = BIT(len(even_res))
odd_bit = BIT(len(odd_res))
for i in range(q):
if query[i][0] == 1:
_, pos, cost = query[i]
pos -= 1
if begin[pos] % 2 == 0:
even_bit.add(begin[pos] // 2, (end[pos] + 1) // 2, cost)
odd_bit.add(begin[pos] // 2, end[pos] // 2, -cost)
else:
odd_bit.add(begin[pos] // 2, end[pos] // 2, cost)
even_bit.add((begin[pos] + 1) // 2, end[pos] // 2, -cost)
else:
_, pos = query[i]
pos -= 1
if begin[pos] % 2 == 0:
ans = even_bit.get_val(begin[pos] // 2)
else:
ans = odd_bit.get_val(begin[pos] // 2)
print(ans + init_cost[pos])
```
| 94,729 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Iahub likes trees very much. Recently he discovered an interesting tree named propagating tree. The tree consists of n nodes numbered from 1 to n, each node i having an initial value ai. The root of the tree is node 1.
This tree has a special property: when a value val is added to a value of node i, the value -val is added to values of all the children of node i. Note that when you add value -val to a child of node i, you also add -(-val) to all children of the child of node i and so on. Look an example explanation to understand better how it works.
This tree supports two types of queries:
* "1 x val" — val is added to the value of node x;
* "2 x" — print the current value of node x.
In order to help Iahub understand the tree better, you must answer m queries of the preceding type.
Input
The first line contains two integers n and m (1 ≤ n, m ≤ 200000). The second line contains n integers a1, a2, ..., an (1 ≤ ai ≤ 1000). Each of the next n–1 lines contains two integers vi and ui (1 ≤ vi, ui ≤ n), meaning that there is an edge between nodes vi and ui.
Each of the next m lines contains a query in the format described above. It is guaranteed that the following constraints hold for all queries: 1 ≤ x ≤ n, 1 ≤ val ≤ 1000.
Output
For each query of type two (print the value of node x) you must print the answer to the query on a separate line. The queries must be answered in the order given in the input.
Examples
Input
5 5
1 2 1 1 2
1 2
1 3
2 4
2 5
1 2 3
1 1 2
2 1
2 2
2 4
Output
3
3
0
Note
The values of the nodes are [1, 2, 1, 1, 2] at the beginning.
Then value 3 is added to node 2. It propagates and value -3 is added to it's sons, node 4 and node 5. Then it cannot propagate any more. So the values of the nodes are [1, 5, 1, - 2, - 1].
Then value 2 is added to node 1. It propagates and value -2 is added to it's sons, node 2 and node 3. From node 2 it propagates again, adding value 2 to it's sons, node 4 and node 5. Node 3 has no sons, so it cannot propagate from there. The values of the nodes are [3, 3, - 1, 0, 1].
You can see all the definitions about the tree at the following link: http://en.wikipedia.org/wiki/Tree_(graph_theory)
Submitted Solution:
```
from sys import setrecursionlimit
import threading
setrecursionlimit(10 ** 9)
threading.stack_size(67108864)
__author__ = 'Pavel Mavrin'
n, m = [int(x) for x in input().split()]
a = [int(x) for x in input().split()]
nb = [[] for x in range(n)]
for i in range(n - 1):
x, y = [int(x) - 1 for x in input().split()]
nb[x].append(y)
nb[y].append(x)
p = [0] * (2 * n)
l = [0] * n
r = [0] * n
c = 0
def dfs(i, parent):
global c
global p
l[i] = c
p[c] = i
c += 1
for j in nb[i]:
if j != parent:
dfs(j, i)
p[c] = i
c += 1
r[i] = c
def make_tree(l, r):
if r == l + 1:
if l % 2 == 0:
return [nonode, nonode, a[p[l]]]
else:
return [nonode, nonode, -a[p[l]]]
else:
m = (l + r) // 2
ll = make_tree(l, m)
rr = make_tree(m, r)
return [ll, rr, 0]
def add(tree, l, r, a, b, val):
if l >= b or a >= r:
return
if l >= a and r <= b:
tree[2] += val
else:
m = (l + r) // 2
tree[0][2] += tree[2]
tree[1][2] += tree[2]
add(tree[0], l, m, a, b, val)
add(tree[1], m, r, a, b, val)
tree[2] = 0
def get(tree, l, r, i):
if r == l + 1:
return tree[2]
m = (l + r) // 2
if i < m:
return tree[2] + get(tree[0], l, m, i)
else:
return tree[2] + get(tree[1], m, r, i)
#print([get(tree, 0, 2 * n, i) for i in range(2 * n)])
def main():
dfs(0, -1)
nonode = [None, None, 0, 0]
tree = make_tree(0, 2 * n)
for i in range(m):
z = [int(x) for x in input().split()]
if z[0] == 1:
if l[z[1] - 1] % 2 == 0:
add(tree, 0, 2 * n, l[z[1] - 1], r[z[1] - 1], z[2])
else:
add(tree, 0, 2 * n, l[z[1] - 1], r[z[1] - 1], -z[2])
# print([get(tree, 0, 2 * n, i) for i in range(2 * n)])
else:
zz = get(tree, 0, 2 * n, l[z[1] - 1])
if l[z[1] - 1] % 2 == 0:
print(zz)
else:
print(-zz)
thread = threading.Thread(target=main)
thread.start()
```
No
| 94,730 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Iahub likes trees very much. Recently he discovered an interesting tree named propagating tree. The tree consists of n nodes numbered from 1 to n, each node i having an initial value ai. The root of the tree is node 1.
This tree has a special property: when a value val is added to a value of node i, the value -val is added to values of all the children of node i. Note that when you add value -val to a child of node i, you also add -(-val) to all children of the child of node i and so on. Look an example explanation to understand better how it works.
This tree supports two types of queries:
* "1 x val" — val is added to the value of node x;
* "2 x" — print the current value of node x.
In order to help Iahub understand the tree better, you must answer m queries of the preceding type.
Input
The first line contains two integers n and m (1 ≤ n, m ≤ 200000). The second line contains n integers a1, a2, ..., an (1 ≤ ai ≤ 1000). Each of the next n–1 lines contains two integers vi and ui (1 ≤ vi, ui ≤ n), meaning that there is an edge between nodes vi and ui.
Each of the next m lines contains a query in the format described above. It is guaranteed that the following constraints hold for all queries: 1 ≤ x ≤ n, 1 ≤ val ≤ 1000.
Output
For each query of type two (print the value of node x) you must print the answer to the query on a separate line. The queries must be answered in the order given in the input.
Examples
Input
5 5
1 2 1 1 2
1 2
1 3
2 4
2 5
1 2 3
1 1 2
2 1
2 2
2 4
Output
3
3
0
Note
The values of the nodes are [1, 2, 1, 1, 2] at the beginning.
Then value 3 is added to node 2. It propagates and value -3 is added to it's sons, node 4 and node 5. Then it cannot propagate any more. So the values of the nodes are [1, 5, 1, - 2, - 1].
Then value 2 is added to node 1. It propagates and value -2 is added to it's sons, node 2 and node 3. From node 2 it propagates again, adding value 2 to it's sons, node 4 and node 5. Node 3 has no sons, so it cannot propagate from there. The values of the nodes are [3, 3, - 1, 0, 1].
You can see all the definitions about the tree at the following link: http://en.wikipedia.org/wiki/Tree_(graph_theory)
Submitted Solution:
```
n,m = map(int,input().split())
values = list(map(int,input().split()))
rebra = []
for i in range(n-1):
rebra.append(list(map(int,input().split())))
zapr = []
for i in range(m-1):
z = list(map(int,input().split()))
if z[0] == 1:
v = -z[2]
values[z[1]-1] -= v
for j in range(z[1],n):
for e in rebra:
if e[0] == j: #2
values[e[1]-1] += v
v = -v
else:
zapr.append(values[z[1]-1])
for i in zapr:
print(i)
```
No
| 94,731 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Iahub likes trees very much. Recently he discovered an interesting tree named propagating tree. The tree consists of n nodes numbered from 1 to n, each node i having an initial value ai. The root of the tree is node 1.
This tree has a special property: when a value val is added to a value of node i, the value -val is added to values of all the children of node i. Note that when you add value -val to a child of node i, you also add -(-val) to all children of the child of node i and so on. Look an example explanation to understand better how it works.
This tree supports two types of queries:
* "1 x val" — val is added to the value of node x;
* "2 x" — print the current value of node x.
In order to help Iahub understand the tree better, you must answer m queries of the preceding type.
Input
The first line contains two integers n and m (1 ≤ n, m ≤ 200000). The second line contains n integers a1, a2, ..., an (1 ≤ ai ≤ 1000). Each of the next n–1 lines contains two integers vi and ui (1 ≤ vi, ui ≤ n), meaning that there is an edge between nodes vi and ui.
Each of the next m lines contains a query in the format described above. It is guaranteed that the following constraints hold for all queries: 1 ≤ x ≤ n, 1 ≤ val ≤ 1000.
Output
For each query of type two (print the value of node x) you must print the answer to the query on a separate line. The queries must be answered in the order given in the input.
Examples
Input
5 5
1 2 1 1 2
1 2
1 3
2 4
2 5
1 2 3
1 1 2
2 1
2 2
2 4
Output
3
3
0
Note
The values of the nodes are [1, 2, 1, 1, 2] at the beginning.
Then value 3 is added to node 2. It propagates and value -3 is added to it's sons, node 4 and node 5. Then it cannot propagate any more. So the values of the nodes are [1, 5, 1, - 2, - 1].
Then value 2 is added to node 1. It propagates and value -2 is added to it's sons, node 2 and node 3. From node 2 it propagates again, adding value 2 to it's sons, node 4 and node 5. Node 3 has no sons, so it cannot propagate from there. The values of the nodes are [3, 3, - 1, 0, 1].
You can see all the definitions about the tree at the following link: http://en.wikipedia.org/wiki/Tree_(graph_theory)
Submitted Solution:
```
n,m = map(int,input().split())
values = list(map(int,input().split()))
rebra = []
for i in range(n-1):
rebra.append(list(map(int,input().split())))
zapr = []
for i in range(m):
z = list(map(int,input().split()))
if z[0] == 1:
v = -z[2]
values[z[1]-1] -= v
for j in range(z[1],n):
for e in rebra:
if e[0] == j: #2
values[e[1]-1] += v
v = -v
else:
zapr.append(values[z[1]-1])
for i in zapr:
print(i)
```
No
| 94,732 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Iahub likes trees very much. Recently he discovered an interesting tree named propagating tree. The tree consists of n nodes numbered from 1 to n, each node i having an initial value ai. The root of the tree is node 1.
This tree has a special property: when a value val is added to a value of node i, the value -val is added to values of all the children of node i. Note that when you add value -val to a child of node i, you also add -(-val) to all children of the child of node i and so on. Look an example explanation to understand better how it works.
This tree supports two types of queries:
* "1 x val" — val is added to the value of node x;
* "2 x" — print the current value of node x.
In order to help Iahub understand the tree better, you must answer m queries of the preceding type.
Input
The first line contains two integers n and m (1 ≤ n, m ≤ 200000). The second line contains n integers a1, a2, ..., an (1 ≤ ai ≤ 1000). Each of the next n–1 lines contains two integers vi and ui (1 ≤ vi, ui ≤ n), meaning that there is an edge between nodes vi and ui.
Each of the next m lines contains a query in the format described above. It is guaranteed that the following constraints hold for all queries: 1 ≤ x ≤ n, 1 ≤ val ≤ 1000.
Output
For each query of type two (print the value of node x) you must print the answer to the query on a separate line. The queries must be answered in the order given in the input.
Examples
Input
5 5
1 2 1 1 2
1 2
1 3
2 4
2 5
1 2 3
1 1 2
2 1
2 2
2 4
Output
3
3
0
Note
The values of the nodes are [1, 2, 1, 1, 2] at the beginning.
Then value 3 is added to node 2. It propagates and value -3 is added to it's sons, node 4 and node 5. Then it cannot propagate any more. So the values of the nodes are [1, 5, 1, - 2, - 1].
Then value 2 is added to node 1. It propagates and value -2 is added to it's sons, node 2 and node 3. From node 2 it propagates again, adding value 2 to it's sons, node 4 and node 5. Node 3 has no sons, so it cannot propagate from there. The values of the nodes are [3, 3, - 1, 0, 1].
You can see all the definitions about the tree at the following link: http://en.wikipedia.org/wiki/Tree_(graph_theory)
Submitted Solution:
```
n,m = map(int,input().split())
values = list(map(int,input().split()))
rebra = []
for i in range(n-1):
rebra.append(list(map(int,input().split())))
zapr = []
for i in range(m):
z = list(map(int,input().split()))
if z[0] == 1:
v = -z[2]
values[z[1]-1] -= v
for j in range(z[1],n+1):
for e in rebra:
if e[0] == j: #2
values[e[1]-1] += v
v = -v
else:
zapr.append(values[z[1]-1])
for i in zapr:
print(i)
```
No
| 94,733 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Valera takes part in the Berland Marathon. The marathon race starts at the stadium that can be represented on the plane as a square whose lower left corner is located at point with coordinates (0, 0) and the length of the side equals a meters. The sides of the square are parallel to coordinate axes.
As the length of the marathon race is very long, Valera needs to have extra drink during the race. The coach gives Valera a bottle of drink each d meters of the path. We know that Valera starts at the point with coordinates (0, 0) and runs counter-clockwise. That is, when Valera covers a meters, he reaches the point with coordinates (a, 0). We also know that the length of the marathon race equals nd + 0.5 meters.
Help Valera's coach determine where he should be located to help Valera. Specifically, determine the coordinates of Valera's positions when he covers d, 2·d, ..., n·d meters.
Input
The first line contains two space-separated real numbers a and d (1 ≤ a, d ≤ 105), given with precision till 4 decimal digits after the decimal point. Number a denotes the length of the square's side that describes the stadium. Number d shows that after each d meters Valera gets an extra drink.
The second line contains integer n (1 ≤ n ≤ 105) showing that Valera needs an extra drink n times.
Output
Print n lines, each line should contain two real numbers xi and yi, separated by a space. Numbers xi and yi in the i-th line mean that Valera is at point with coordinates (xi, yi) after he covers i·d meters. Your solution will be considered correct if the absolute or relative error doesn't exceed 10 - 4.
Note, that this problem have huge amount of output data. Please, do not use cout stream for output in this problem.
Examples
Input
2 5
2
Output
1.0000000000 2.0000000000
2.0000000000 0.0000000000
Input
4.147 2.8819
6
Output
2.8819000000 0.0000000000
4.1470000000 1.6168000000
3.7953000000 4.1470000000
0.9134000000 4.1470000000
0.0000000000 2.1785000000
0.7034000000 0.0000000000
Tags: implementation, math
Correct Solution:
```
import math
a, d = map(float, input().split())
n = int(input())
for p in (math.fmod(i * d, 4 * a) for i in range(1, n + 1)):
if p <= a:
x, y = p, 0
elif p <= 2 * a:
x, y = a, p - a
elif p <= 3 * a:
x, y = 3 * a - p, a
else:
x, y = 0, 4 * a - p
print("{:.10f} {:.10f}".format(x, y))
```
| 94,734 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Valera takes part in the Berland Marathon. The marathon race starts at the stadium that can be represented on the plane as a square whose lower left corner is located at point with coordinates (0, 0) and the length of the side equals a meters. The sides of the square are parallel to coordinate axes.
As the length of the marathon race is very long, Valera needs to have extra drink during the race. The coach gives Valera a bottle of drink each d meters of the path. We know that Valera starts at the point with coordinates (0, 0) and runs counter-clockwise. That is, when Valera covers a meters, he reaches the point with coordinates (a, 0). We also know that the length of the marathon race equals nd + 0.5 meters.
Help Valera's coach determine where he should be located to help Valera. Specifically, determine the coordinates of Valera's positions when he covers d, 2·d, ..., n·d meters.
Input
The first line contains two space-separated real numbers a and d (1 ≤ a, d ≤ 105), given with precision till 4 decimal digits after the decimal point. Number a denotes the length of the square's side that describes the stadium. Number d shows that after each d meters Valera gets an extra drink.
The second line contains integer n (1 ≤ n ≤ 105) showing that Valera needs an extra drink n times.
Output
Print n lines, each line should contain two real numbers xi and yi, separated by a space. Numbers xi and yi in the i-th line mean that Valera is at point with coordinates (xi, yi) after he covers i·d meters. Your solution will be considered correct if the absolute or relative error doesn't exceed 10 - 4.
Note, that this problem have huge amount of output data. Please, do not use cout stream for output in this problem.
Examples
Input
2 5
2
Output
1.0000000000 2.0000000000
2.0000000000 0.0000000000
Input
4.147 2.8819
6
Output
2.8819000000 0.0000000000
4.1470000000 1.6168000000
3.7953000000 4.1470000000
0.9134000000 4.1470000000
0.0000000000 2.1785000000
0.7034000000 0.0000000000
Tags: implementation, math
Correct Solution:
```
a, d = map(float, input().split())
n = int(input())
t = 0
for i in range(n):
t = (t+d) % (4*a)
if t < a:
print(t, 0)
continue
if t < 2 * a:
print(a, t-a)
continue
if t < 3 * a:
print(3*a-t, a)
continue
if t < 4 * a:
print(0, 4*a-t)
```
| 94,735 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Valera takes part in the Berland Marathon. The marathon race starts at the stadium that can be represented on the plane as a square whose lower left corner is located at point with coordinates (0, 0) and the length of the side equals a meters. The sides of the square are parallel to coordinate axes.
As the length of the marathon race is very long, Valera needs to have extra drink during the race. The coach gives Valera a bottle of drink each d meters of the path. We know that Valera starts at the point with coordinates (0, 0) and runs counter-clockwise. That is, when Valera covers a meters, he reaches the point with coordinates (a, 0). We also know that the length of the marathon race equals nd + 0.5 meters.
Help Valera's coach determine where he should be located to help Valera. Specifically, determine the coordinates of Valera's positions when he covers d, 2·d, ..., n·d meters.
Input
The first line contains two space-separated real numbers a and d (1 ≤ a, d ≤ 105), given with precision till 4 decimal digits after the decimal point. Number a denotes the length of the square's side that describes the stadium. Number d shows that after each d meters Valera gets an extra drink.
The second line contains integer n (1 ≤ n ≤ 105) showing that Valera needs an extra drink n times.
Output
Print n lines, each line should contain two real numbers xi and yi, separated by a space. Numbers xi and yi in the i-th line mean that Valera is at point with coordinates (xi, yi) after he covers i·d meters. Your solution will be considered correct if the absolute or relative error doesn't exceed 10 - 4.
Note, that this problem have huge amount of output data. Please, do not use cout stream for output in this problem.
Examples
Input
2 5
2
Output
1.0000000000 2.0000000000
2.0000000000 0.0000000000
Input
4.147 2.8819
6
Output
2.8819000000 0.0000000000
4.1470000000 1.6168000000
3.7953000000 4.1470000000
0.9134000000 4.1470000000
0.0000000000 2.1785000000
0.7034000000 0.0000000000
Tags: implementation, math
Correct Solution:
```
from math import floor
a, d = map(float, input().split())
n = int(input())
res = []
for i in range(n):
rec = i*d + d
tra = floor(rec/a) % 4
seg = rec - floor(rec/a)*a
# print("D>",rec, tra, seg)
if tra == 0:
res.append("%.8f %.8f" % (seg, 0.0))
elif tra == 1:
res.append("%.8f %.8f" % (a, seg))
elif tra == 2:
res.append("%.8f %.8f" % (a-seg, a))
elif tra == 3:
res.append("%.8f %.8f" % (0.0, a-seg))
print("\n".join(res))
```
| 94,736 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Valera takes part in the Berland Marathon. The marathon race starts at the stadium that can be represented on the plane as a square whose lower left corner is located at point with coordinates (0, 0) and the length of the side equals a meters. The sides of the square are parallel to coordinate axes.
As the length of the marathon race is very long, Valera needs to have extra drink during the race. The coach gives Valera a bottle of drink each d meters of the path. We know that Valera starts at the point with coordinates (0, 0) and runs counter-clockwise. That is, when Valera covers a meters, he reaches the point with coordinates (a, 0). We also know that the length of the marathon race equals nd + 0.5 meters.
Help Valera's coach determine where he should be located to help Valera. Specifically, determine the coordinates of Valera's positions when he covers d, 2·d, ..., n·d meters.
Input
The first line contains two space-separated real numbers a and d (1 ≤ a, d ≤ 105), given with precision till 4 decimal digits after the decimal point. Number a denotes the length of the square's side that describes the stadium. Number d shows that after each d meters Valera gets an extra drink.
The second line contains integer n (1 ≤ n ≤ 105) showing that Valera needs an extra drink n times.
Output
Print n lines, each line should contain two real numbers xi and yi, separated by a space. Numbers xi and yi in the i-th line mean that Valera is at point with coordinates (xi, yi) after he covers i·d meters. Your solution will be considered correct if the absolute or relative error doesn't exceed 10 - 4.
Note, that this problem have huge amount of output data. Please, do not use cout stream for output in this problem.
Examples
Input
2 5
2
Output
1.0000000000 2.0000000000
2.0000000000 0.0000000000
Input
4.147 2.8819
6
Output
2.8819000000 0.0000000000
4.1470000000 1.6168000000
3.7953000000 4.1470000000
0.9134000000 4.1470000000
0.0000000000 2.1785000000
0.7034000000 0.0000000000
Tags: implementation, math
Correct Solution:
```
def main():
a, d = map(float, input().split())
ai, di = (int(_ * 1e4 + .1) for _ in (a, d))
a2, a3, a4 = (ai * _ for _ in (2, 3, 4))
n, sa = int(input()), "%.10f" % a
for t in range(di, n * di + 5001, di):
t %= a4
if t <= a2:
if t <= ai:
print("%.10f 0.0000000000" % (t * 1e-4))
else:
print(sa, "%.10f" % ((t - ai) * 1e-4))
else:
if t <= a3:
print("%.10f" % ((-t) % ai * 1e-4), sa)
else:
print("0.0000000000 %.10f" % ((- t) % ai * 1e-4))
if __name__ == '__main__':
main()
```
| 94,737 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Valera takes part in the Berland Marathon. The marathon race starts at the stadium that can be represented on the plane as a square whose lower left corner is located at point with coordinates (0, 0) and the length of the side equals a meters. The sides of the square are parallel to coordinate axes.
As the length of the marathon race is very long, Valera needs to have extra drink during the race. The coach gives Valera a bottle of drink each d meters of the path. We know that Valera starts at the point with coordinates (0, 0) and runs counter-clockwise. That is, when Valera covers a meters, he reaches the point with coordinates (a, 0). We also know that the length of the marathon race equals nd + 0.5 meters.
Help Valera's coach determine where he should be located to help Valera. Specifically, determine the coordinates of Valera's positions when he covers d, 2·d, ..., n·d meters.
Input
The first line contains two space-separated real numbers a and d (1 ≤ a, d ≤ 105), given with precision till 4 decimal digits after the decimal point. Number a denotes the length of the square's side that describes the stadium. Number d shows that after each d meters Valera gets an extra drink.
The second line contains integer n (1 ≤ n ≤ 105) showing that Valera needs an extra drink n times.
Output
Print n lines, each line should contain two real numbers xi and yi, separated by a space. Numbers xi and yi in the i-th line mean that Valera is at point with coordinates (xi, yi) after he covers i·d meters. Your solution will be considered correct if the absolute or relative error doesn't exceed 10 - 4.
Note, that this problem have huge amount of output data. Please, do not use cout stream for output in this problem.
Examples
Input
2 5
2
Output
1.0000000000 2.0000000000
2.0000000000 0.0000000000
Input
4.147 2.8819
6
Output
2.8819000000 0.0000000000
4.1470000000 1.6168000000
3.7953000000 4.1470000000
0.9134000000 4.1470000000
0.0000000000 2.1785000000
0.7034000000 0.0000000000
Tags: implementation, math
Correct Solution:
```
[a, d], n, tmp = map(float, input().split()), int(input()), 0
for i in range(n):
tmp = (tmp + d) % (4 * a)
if tmp <= a:
print(tmp, 0)
elif tmp <= 2 * a:
print(a, tmp - a)
elif tmp <= 3 * a:
print(3 * a - tmp, a)
else:
print(0, 4 * a - tmp)
```
| 94,738 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Valera takes part in the Berland Marathon. The marathon race starts at the stadium that can be represented on the plane as a square whose lower left corner is located at point with coordinates (0, 0) and the length of the side equals a meters. The sides of the square are parallel to coordinate axes.
As the length of the marathon race is very long, Valera needs to have extra drink during the race. The coach gives Valera a bottle of drink each d meters of the path. We know that Valera starts at the point with coordinates (0, 0) and runs counter-clockwise. That is, when Valera covers a meters, he reaches the point with coordinates (a, 0). We also know that the length of the marathon race equals nd + 0.5 meters.
Help Valera's coach determine where he should be located to help Valera. Specifically, determine the coordinates of Valera's positions when he covers d, 2·d, ..., n·d meters.
Input
The first line contains two space-separated real numbers a and d (1 ≤ a, d ≤ 105), given with precision till 4 decimal digits after the decimal point. Number a denotes the length of the square's side that describes the stadium. Number d shows that after each d meters Valera gets an extra drink.
The second line contains integer n (1 ≤ n ≤ 105) showing that Valera needs an extra drink n times.
Output
Print n lines, each line should contain two real numbers xi and yi, separated by a space. Numbers xi and yi in the i-th line mean that Valera is at point with coordinates (xi, yi) after he covers i·d meters. Your solution will be considered correct if the absolute or relative error doesn't exceed 10 - 4.
Note, that this problem have huge amount of output data. Please, do not use cout stream for output in this problem.
Examples
Input
2 5
2
Output
1.0000000000 2.0000000000
2.0000000000 0.0000000000
Input
4.147 2.8819
6
Output
2.8819000000 0.0000000000
4.1470000000 1.6168000000
3.7953000000 4.1470000000
0.9134000000 4.1470000000
0.0000000000 2.1785000000
0.7034000000 0.0000000000
Tags: implementation, math
Correct Solution:
```
a,b = [float(x) for x in input().split()]
n = int(input())
for i in range(1,n+1):
rem = (i*b)%(4*a)
print(*[(rem,0),(a,rem-a),(3*a-rem,a),(0,4*a-rem)][int(rem//a)])
```
| 94,739 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Valera takes part in the Berland Marathon. The marathon race starts at the stadium that can be represented on the plane as a square whose lower left corner is located at point with coordinates (0, 0) and the length of the side equals a meters. The sides of the square are parallel to coordinate axes.
As the length of the marathon race is very long, Valera needs to have extra drink during the race. The coach gives Valera a bottle of drink each d meters of the path. We know that Valera starts at the point with coordinates (0, 0) and runs counter-clockwise. That is, when Valera covers a meters, he reaches the point with coordinates (a, 0). We also know that the length of the marathon race equals nd + 0.5 meters.
Help Valera's coach determine where he should be located to help Valera. Specifically, determine the coordinates of Valera's positions when he covers d, 2·d, ..., n·d meters.
Input
The first line contains two space-separated real numbers a and d (1 ≤ a, d ≤ 105), given with precision till 4 decimal digits after the decimal point. Number a denotes the length of the square's side that describes the stadium. Number d shows that after each d meters Valera gets an extra drink.
The second line contains integer n (1 ≤ n ≤ 105) showing that Valera needs an extra drink n times.
Output
Print n lines, each line should contain two real numbers xi and yi, separated by a space. Numbers xi and yi in the i-th line mean that Valera is at point with coordinates (xi, yi) after he covers i·d meters. Your solution will be considered correct if the absolute or relative error doesn't exceed 10 - 4.
Note, that this problem have huge amount of output data. Please, do not use cout stream for output in this problem.
Examples
Input
2 5
2
Output
1.0000000000 2.0000000000
2.0000000000 0.0000000000
Input
4.147 2.8819
6
Output
2.8819000000 0.0000000000
4.1470000000 1.6168000000
3.7953000000 4.1470000000
0.9134000000 4.1470000000
0.0000000000 2.1785000000
0.7034000000 0.0000000000
Tags: implementation, math
Correct Solution:
```
a,d = [float(i) for i in input().split()]
n = int(input())
d%=4*a
start = 0
seg = 0
for i in range(n):
start += d
lengths = int(start/a)
start = start%a
seg = (seg+lengths)%4
if seg==0:
print(start, 0)
elif seg==1:
print(a, start)
elif seg==2:
print(a-start, a)
else:
print(0, a-start)
```
| 94,740 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Valera takes part in the Berland Marathon. The marathon race starts at the stadium that can be represented on the plane as a square whose lower left corner is located at point with coordinates (0, 0) and the length of the side equals a meters. The sides of the square are parallel to coordinate axes.
As the length of the marathon race is very long, Valera needs to have extra drink during the race. The coach gives Valera a bottle of drink each d meters of the path. We know that Valera starts at the point with coordinates (0, 0) and runs counter-clockwise. That is, when Valera covers a meters, he reaches the point with coordinates (a, 0). We also know that the length of the marathon race equals nd + 0.5 meters.
Help Valera's coach determine where he should be located to help Valera. Specifically, determine the coordinates of Valera's positions when he covers d, 2·d, ..., n·d meters.
Input
The first line contains two space-separated real numbers a and d (1 ≤ a, d ≤ 105), given with precision till 4 decimal digits after the decimal point. Number a denotes the length of the square's side that describes the stadium. Number d shows that after each d meters Valera gets an extra drink.
The second line contains integer n (1 ≤ n ≤ 105) showing that Valera needs an extra drink n times.
Output
Print n lines, each line should contain two real numbers xi and yi, separated by a space. Numbers xi and yi in the i-th line mean that Valera is at point with coordinates (xi, yi) after he covers i·d meters. Your solution will be considered correct if the absolute or relative error doesn't exceed 10 - 4.
Note, that this problem have huge amount of output data. Please, do not use cout stream for output in this problem.
Examples
Input
2 5
2
Output
1.0000000000 2.0000000000
2.0000000000 0.0000000000
Input
4.147 2.8819
6
Output
2.8819000000 0.0000000000
4.1470000000 1.6168000000
3.7953000000 4.1470000000
0.9134000000 4.1470000000
0.0000000000 2.1785000000
0.7034000000 0.0000000000
Tags: implementation, math
Correct Solution:
```
from decimal import Decimal
a, d=map(Decimal, input().split())
n=int(input())
tot=Decimal(0.0)
x=Decimal(); y=Decimal()
for i in range(n):
tot+=d
tot%=4*a
if tot<a: x=tot; y=0.0
elif tot<2*a: x=a; y=tot-a
elif tot<3*a: x=3*a-tot; y=a
else: x=0.0; y=4*a-tot
print(x, end=' '); print(y)
```
| 94,741 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Valera takes part in the Berland Marathon. The marathon race starts at the stadium that can be represented on the plane as a square whose lower left corner is located at point with coordinates (0, 0) and the length of the side equals a meters. The sides of the square are parallel to coordinate axes.
As the length of the marathon race is very long, Valera needs to have extra drink during the race. The coach gives Valera a bottle of drink each d meters of the path. We know that Valera starts at the point with coordinates (0, 0) and runs counter-clockwise. That is, when Valera covers a meters, he reaches the point with coordinates (a, 0). We also know that the length of the marathon race equals nd + 0.5 meters.
Help Valera's coach determine where he should be located to help Valera. Specifically, determine the coordinates of Valera's positions when he covers d, 2·d, ..., n·d meters.
Input
The first line contains two space-separated real numbers a and d (1 ≤ a, d ≤ 105), given with precision till 4 decimal digits after the decimal point. Number a denotes the length of the square's side that describes the stadium. Number d shows that after each d meters Valera gets an extra drink.
The second line contains integer n (1 ≤ n ≤ 105) showing that Valera needs an extra drink n times.
Output
Print n lines, each line should contain two real numbers xi and yi, separated by a space. Numbers xi and yi in the i-th line mean that Valera is at point with coordinates (xi, yi) after he covers i·d meters. Your solution will be considered correct if the absolute or relative error doesn't exceed 10 - 4.
Note, that this problem have huge amount of output data. Please, do not use cout stream for output in this problem.
Examples
Input
2 5
2
Output
1.0000000000 2.0000000000
2.0000000000 0.0000000000
Input
4.147 2.8819
6
Output
2.8819000000 0.0000000000
4.1470000000 1.6168000000
3.7953000000 4.1470000000
0.9134000000 4.1470000000
0.0000000000 2.1785000000
0.7034000000 0.0000000000
Submitted Solution:
```
def setPoint(point, a):
p = point
x = 0
y = 0
if p <= a:
x = p
y = 0
elif p <= a*2:
x = a
y = p - a
elif p <= a*3:
x = a*3 - p
y = a
else:
x = 0
y = a*4 - p
x = int(x*100000)/100000
y = int(y*100000)/100000
return str(x) + ' ' + str(y)
a, d = map(float, input().split())
n = int(input())
curP = 0
for l in range(0, n):
curP += d
curP = curP % (a*4)
print(setPoint(curP, a))
```
Yes
| 94,742 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Valera takes part in the Berland Marathon. The marathon race starts at the stadium that can be represented on the plane as a square whose lower left corner is located at point with coordinates (0, 0) and the length of the side equals a meters. The sides of the square are parallel to coordinate axes.
As the length of the marathon race is very long, Valera needs to have extra drink during the race. The coach gives Valera a bottle of drink each d meters of the path. We know that Valera starts at the point with coordinates (0, 0) and runs counter-clockwise. That is, when Valera covers a meters, he reaches the point with coordinates (a, 0). We also know that the length of the marathon race equals nd + 0.5 meters.
Help Valera's coach determine where he should be located to help Valera. Specifically, determine the coordinates of Valera's positions when he covers d, 2·d, ..., n·d meters.
Input
The first line contains two space-separated real numbers a and d (1 ≤ a, d ≤ 105), given with precision till 4 decimal digits after the decimal point. Number a denotes the length of the square's side that describes the stadium. Number d shows that after each d meters Valera gets an extra drink.
The second line contains integer n (1 ≤ n ≤ 105) showing that Valera needs an extra drink n times.
Output
Print n lines, each line should contain two real numbers xi and yi, separated by a space. Numbers xi and yi in the i-th line mean that Valera is at point with coordinates (xi, yi) after he covers i·d meters. Your solution will be considered correct if the absolute or relative error doesn't exceed 10 - 4.
Note, that this problem have huge amount of output data. Please, do not use cout stream for output in this problem.
Examples
Input
2 5
2
Output
1.0000000000 2.0000000000
2.0000000000 0.0000000000
Input
4.147 2.8819
6
Output
2.8819000000 0.0000000000
4.1470000000 1.6168000000
3.7953000000 4.1470000000
0.9134000000 4.1470000000
0.0000000000 2.1785000000
0.7034000000 0.0000000000
Submitted Solution:
```
a, d = map(float, input().split())
n = int(input())
def coordinates(s):
if s <= a:
return (s, 0)
elif s <= 2*a:
return (a, s-a)
elif s <= 3*a:
return (3*a - s, a)
else:
return (0, 4*a - s)
for i in range(1, n+1):
print("%f %f" % coordinates(i*d % (4*a)))
```
Yes
| 94,743 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Valera takes part in the Berland Marathon. The marathon race starts at the stadium that can be represented on the plane as a square whose lower left corner is located at point with coordinates (0, 0) and the length of the side equals a meters. The sides of the square are parallel to coordinate axes.
As the length of the marathon race is very long, Valera needs to have extra drink during the race. The coach gives Valera a bottle of drink each d meters of the path. We know that Valera starts at the point with coordinates (0, 0) and runs counter-clockwise. That is, when Valera covers a meters, he reaches the point with coordinates (a, 0). We also know that the length of the marathon race equals nd + 0.5 meters.
Help Valera's coach determine where he should be located to help Valera. Specifically, determine the coordinates of Valera's positions when he covers d, 2·d, ..., n·d meters.
Input
The first line contains two space-separated real numbers a and d (1 ≤ a, d ≤ 105), given with precision till 4 decimal digits after the decimal point. Number a denotes the length of the square's side that describes the stadium. Number d shows that after each d meters Valera gets an extra drink.
The second line contains integer n (1 ≤ n ≤ 105) showing that Valera needs an extra drink n times.
Output
Print n lines, each line should contain two real numbers xi and yi, separated by a space. Numbers xi and yi in the i-th line mean that Valera is at point with coordinates (xi, yi) after he covers i·d meters. Your solution will be considered correct if the absolute or relative error doesn't exceed 10 - 4.
Note, that this problem have huge amount of output data. Please, do not use cout stream for output in this problem.
Examples
Input
2 5
2
Output
1.0000000000 2.0000000000
2.0000000000 0.0000000000
Input
4.147 2.8819
6
Output
2.8819000000 0.0000000000
4.1470000000 1.6168000000
3.7953000000 4.1470000000
0.9134000000 4.1470000000
0.0000000000 2.1785000000
0.7034000000 0.0000000000
Submitted Solution:
```
a,d=map(float,input().split())
n=int(input())
for i in range(1,n+1):
s=(d*i)%(4*a)
if s<=a:
print(s,0)
elif s<=2*a:
print(a,s-a)
elif s<=3*a:
print(3*a-s,a)
else:
print(0,4*a-s)
```
Yes
| 94,744 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Valera takes part in the Berland Marathon. The marathon race starts at the stadium that can be represented on the plane as a square whose lower left corner is located at point with coordinates (0, 0) and the length of the side equals a meters. The sides of the square are parallel to coordinate axes.
As the length of the marathon race is very long, Valera needs to have extra drink during the race. The coach gives Valera a bottle of drink each d meters of the path. We know that Valera starts at the point with coordinates (0, 0) and runs counter-clockwise. That is, when Valera covers a meters, he reaches the point with coordinates (a, 0). We also know that the length of the marathon race equals nd + 0.5 meters.
Help Valera's coach determine where he should be located to help Valera. Specifically, determine the coordinates of Valera's positions when he covers d, 2·d, ..., n·d meters.
Input
The first line contains two space-separated real numbers a and d (1 ≤ a, d ≤ 105), given with precision till 4 decimal digits after the decimal point. Number a denotes the length of the square's side that describes the stadium. Number d shows that after each d meters Valera gets an extra drink.
The second line contains integer n (1 ≤ n ≤ 105) showing that Valera needs an extra drink n times.
Output
Print n lines, each line should contain two real numbers xi and yi, separated by a space. Numbers xi and yi in the i-th line mean that Valera is at point with coordinates (xi, yi) after he covers i·d meters. Your solution will be considered correct if the absolute or relative error doesn't exceed 10 - 4.
Note, that this problem have huge amount of output data. Please, do not use cout stream for output in this problem.
Examples
Input
2 5
2
Output
1.0000000000 2.0000000000
2.0000000000 0.0000000000
Input
4.147 2.8819
6
Output
2.8819000000 0.0000000000
4.1470000000 1.6168000000
3.7953000000 4.1470000000
0.9134000000 4.1470000000
0.0000000000 2.1785000000
0.7034000000 0.0000000000
Submitted Solution:
```
#!/usr/bin/env python3
# -*- coding: utf-8 -*-
import sys
def main():
a, d =map(lambda x: int(float(x) * 10000 + 1e-6), input().split(' '))
ans = []
for i in range(1, int(input()) + 1):
cur_round_pos = d * i % (a * 4)
if cur_round_pos <= a:
y = 0
x = cur_round_pos / 10000
elif cur_round_pos <= a * 2:
x = a / 10000
y = (cur_round_pos - a) / 10000
elif cur_round_pos <= a * 3:
y = a / 10000
x = (a * 3 - cur_round_pos) / 10000
elif cur_round_pos < a * 4:
x = 0
y = (a * 4 - cur_round_pos) / 10000
ans.append('{} {}'.format(x, y))
print('\n'.join(ans))
if __name__ == '__main__':
sys.exit(main())
```
Yes
| 94,745 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Valera takes part in the Berland Marathon. The marathon race starts at the stadium that can be represented on the plane as a square whose lower left corner is located at point with coordinates (0, 0) and the length of the side equals a meters. The sides of the square are parallel to coordinate axes.
As the length of the marathon race is very long, Valera needs to have extra drink during the race. The coach gives Valera a bottle of drink each d meters of the path. We know that Valera starts at the point with coordinates (0, 0) and runs counter-clockwise. That is, when Valera covers a meters, he reaches the point with coordinates (a, 0). We also know that the length of the marathon race equals nd + 0.5 meters.
Help Valera's coach determine where he should be located to help Valera. Specifically, determine the coordinates of Valera's positions when he covers d, 2·d, ..., n·d meters.
Input
The first line contains two space-separated real numbers a and d (1 ≤ a, d ≤ 105), given with precision till 4 decimal digits after the decimal point. Number a denotes the length of the square's side that describes the stadium. Number d shows that after each d meters Valera gets an extra drink.
The second line contains integer n (1 ≤ n ≤ 105) showing that Valera needs an extra drink n times.
Output
Print n lines, each line should contain two real numbers xi and yi, separated by a space. Numbers xi and yi in the i-th line mean that Valera is at point with coordinates (xi, yi) after he covers i·d meters. Your solution will be considered correct if the absolute or relative error doesn't exceed 10 - 4.
Note, that this problem have huge amount of output data. Please, do not use cout stream for output in this problem.
Examples
Input
2 5
2
Output
1.0000000000 2.0000000000
2.0000000000 0.0000000000
Input
4.147 2.8819
6
Output
2.8819000000 0.0000000000
4.1470000000 1.6168000000
3.7953000000 4.1470000000
0.9134000000 4.1470000000
0.0000000000 2.1785000000
0.7034000000 0.0000000000
Submitted Solution:
```
def setPoint(point, a):
p = point
x = 0
y = 0
cnt = 0
if p <= a:
x = p
y = 0
elif p <= a*2:
x = a
y = p
elif p <= a*3:
x = a*3 - p
y = a
else:
x = 0
y = a*4 - p
return str(x)[:7] + ' ' + str(y)[:7]
a, d = map(float, input().split())
n = int(input())
curP = 0
finish = n*d + 0.5
for l in range(0, n):
curP += d
while curP > a*4:
curP -= a*4
print(setPoint(curP, a))
```
No
| 94,746 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Valera takes part in the Berland Marathon. The marathon race starts at the stadium that can be represented on the plane as a square whose lower left corner is located at point with coordinates (0, 0) and the length of the side equals a meters. The sides of the square are parallel to coordinate axes.
As the length of the marathon race is very long, Valera needs to have extra drink during the race. The coach gives Valera a bottle of drink each d meters of the path. We know that Valera starts at the point with coordinates (0, 0) and runs counter-clockwise. That is, when Valera covers a meters, he reaches the point with coordinates (a, 0). We also know that the length of the marathon race equals nd + 0.5 meters.
Help Valera's coach determine where he should be located to help Valera. Specifically, determine the coordinates of Valera's positions when he covers d, 2·d, ..., n·d meters.
Input
The first line contains two space-separated real numbers a and d (1 ≤ a, d ≤ 105), given with precision till 4 decimal digits after the decimal point. Number a denotes the length of the square's side that describes the stadium. Number d shows that after each d meters Valera gets an extra drink.
The second line contains integer n (1 ≤ n ≤ 105) showing that Valera needs an extra drink n times.
Output
Print n lines, each line should contain two real numbers xi and yi, separated by a space. Numbers xi and yi in the i-th line mean that Valera is at point with coordinates (xi, yi) after he covers i·d meters. Your solution will be considered correct if the absolute or relative error doesn't exceed 10 - 4.
Note, that this problem have huge amount of output data. Please, do not use cout stream for output in this problem.
Examples
Input
2 5
2
Output
1.0000000000 2.0000000000
2.0000000000 0.0000000000
Input
4.147 2.8819
6
Output
2.8819000000 0.0000000000
4.1470000000 1.6168000000
3.7953000000 4.1470000000
0.9134000000 4.1470000000
0.0000000000 2.1785000000
0.7034000000 0.0000000000
Submitted Solution:
```
#!/usr/bin/env python3
# -*- coding: utf-8 -*-
import sys
def main():
a, d =map(lambda x: int(float(x) * 10000), input().split(' '))
ans = []
for i in range(1, int(input()) + 1):
t = d * i % (a * 4)
if t <= a:
y = 0
x = t / 10000
elif t <= a * 2:
x = a / 10000
y = (t - a) / 10000
elif t <= a * 3:
y = a / 10000
x = (a - (t - a * 2)) / 10000
elif t < a * 4:
x = 0
y = (a - (t - a * 3)) / 10000
ans.append('{} {}'.format(x, y))
print('\n'.join(ans))
if __name__ == '__main__':
sys.exit(main())
```
No
| 94,747 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Valera takes part in the Berland Marathon. The marathon race starts at the stadium that can be represented on the plane as a square whose lower left corner is located at point with coordinates (0, 0) and the length of the side equals a meters. The sides of the square are parallel to coordinate axes.
As the length of the marathon race is very long, Valera needs to have extra drink during the race. The coach gives Valera a bottle of drink each d meters of the path. We know that Valera starts at the point with coordinates (0, 0) and runs counter-clockwise. That is, when Valera covers a meters, he reaches the point with coordinates (a, 0). We also know that the length of the marathon race equals nd + 0.5 meters.
Help Valera's coach determine where he should be located to help Valera. Specifically, determine the coordinates of Valera's positions when he covers d, 2·d, ..., n·d meters.
Input
The first line contains two space-separated real numbers a and d (1 ≤ a, d ≤ 105), given with precision till 4 decimal digits after the decimal point. Number a denotes the length of the square's side that describes the stadium. Number d shows that after each d meters Valera gets an extra drink.
The second line contains integer n (1 ≤ n ≤ 105) showing that Valera needs an extra drink n times.
Output
Print n lines, each line should contain two real numbers xi and yi, separated by a space. Numbers xi and yi in the i-th line mean that Valera is at point with coordinates (xi, yi) after he covers i·d meters. Your solution will be considered correct if the absolute or relative error doesn't exceed 10 - 4.
Note, that this problem have huge amount of output data. Please, do not use cout stream for output in this problem.
Examples
Input
2 5
2
Output
1.0000000000 2.0000000000
2.0000000000 0.0000000000
Input
4.147 2.8819
6
Output
2.8819000000 0.0000000000
4.1470000000 1.6168000000
3.7953000000 4.1470000000
0.9134000000 4.1470000000
0.0000000000 2.1785000000
0.7034000000 0.0000000000
Submitted Solution:
```
#!/usr/bin/env python3
# -*- coding: utf-8 -*-
import sys
def main():
a, d =map(lambda x: int(float(x) * 10000), input().split(' '))
for i in range(1, int(input()) + 1):
cur_round_pos = d * i % (a * 4)
if cur_round_pos <= a:
y = 0.0
x = cur_round_pos / 10000
elif cur_round_pos <= a * 2:
x = a / 10000
y = (cur_round_pos - a) / 10000
elif cur_round_pos <= a * 3:
y = a / 10000
x = (a - (cur_round_pos - a * 2)) / 10000
elif cur_round_pos <= a * 4:
x = 0.0
y = (a - (cur_round_pos - a * 3)) / 10000
print(x, end=' ')
print(y)
if __name__ == '__main__':
sys.exit(main())
```
No
| 94,748 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Valera takes part in the Berland Marathon. The marathon race starts at the stadium that can be represented on the plane as a square whose lower left corner is located at point with coordinates (0, 0) and the length of the side equals a meters. The sides of the square are parallel to coordinate axes.
As the length of the marathon race is very long, Valera needs to have extra drink during the race. The coach gives Valera a bottle of drink each d meters of the path. We know that Valera starts at the point with coordinates (0, 0) and runs counter-clockwise. That is, when Valera covers a meters, he reaches the point with coordinates (a, 0). We also know that the length of the marathon race equals nd + 0.5 meters.
Help Valera's coach determine where he should be located to help Valera. Specifically, determine the coordinates of Valera's positions when he covers d, 2·d, ..., n·d meters.
Input
The first line contains two space-separated real numbers a and d (1 ≤ a, d ≤ 105), given with precision till 4 decimal digits after the decimal point. Number a denotes the length of the square's side that describes the stadium. Number d shows that after each d meters Valera gets an extra drink.
The second line contains integer n (1 ≤ n ≤ 105) showing that Valera needs an extra drink n times.
Output
Print n lines, each line should contain two real numbers xi and yi, separated by a space. Numbers xi and yi in the i-th line mean that Valera is at point with coordinates (xi, yi) after he covers i·d meters. Your solution will be considered correct if the absolute or relative error doesn't exceed 10 - 4.
Note, that this problem have huge amount of output data. Please, do not use cout stream for output in this problem.
Examples
Input
2 5
2
Output
1.0000000000 2.0000000000
2.0000000000 0.0000000000
Input
4.147 2.8819
6
Output
2.8819000000 0.0000000000
4.1470000000 1.6168000000
3.7953000000 4.1470000000
0.9134000000 4.1470000000
0.0000000000 2.1785000000
0.7034000000 0.0000000000
Submitted Solution:
```
#!/usr/bin/env python3
# -*- coding: utf-8 -*-
import sys
def main():
a, d =map(lambda x: int(float(x) * 10000 + 1e-6), input().split(' '))
ans = []
for i in range(1, int(input()) + 1):
cur_round_pos = d * i % (a * 4)
if cur_round_pos <= a:
y = 0
x = cur_round_pos / 10000
elif cur_round_pos <= a * 2:
x = a / 10000
y = (cur_round_pos - a) / 10000
elif cur_round_pos <= a * 3:
y = a
x = (a * 3 - cur_round_pos) / 10000
elif cur_round_pos < a * 4:
x = 0
y = (a * 4 - cur_round_pos) / 10000
print('{} {}'.format(x, y))
ans.append('{} {}'.format(x, y))
print('\n'.join(ans))
if __name__ == '__main__':
sys.exit(main())
```
No
| 94,749 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Quite recently a creative student Lesha had a lecture on trees. After the lecture Lesha was inspired and came up with the tree of his own which he called a k-tree.
A k-tree is an infinite rooted tree where:
* each vertex has exactly k children;
* each edge has some weight;
* if we look at the edges that goes from some vertex to its children (exactly k edges), then their weights will equal 1, 2, 3, ..., k.
The picture below shows a part of a 3-tree.
<image>
As soon as Dima, a good friend of Lesha, found out about the tree, he immediately wondered: "How many paths of total weight n (the sum of all weights of the edges in the path) are there, starting from the root of a k-tree and also containing at least one edge of weight at least d?".
Help Dima find an answer to his question. As the number of ways can be rather large, print it modulo 1000000007 (109 + 7).
Input
A single line contains three space-separated integers: n, k and d (1 ≤ n, k ≤ 100; 1 ≤ d ≤ k).
Output
Print a single integer — the answer to the problem modulo 1000000007 (109 + 7).
Examples
Input
3 3 2
Output
3
Input
3 3 3
Output
1
Input
4 3 2
Output
6
Input
4 5 2
Output
7
Tags: dp, implementation, trees
Correct Solution:
```
n,v,d=list(map(int,input().split()))
dp=[[0]*2 for i in range(n+1)]
dp[0][0]=1
for i in range(1,n+1):
for k in range(1,min(i,v)+1):
dp[i][0]+=dp[i-k][0]
if k>=d:
dp[i][1]+=dp[i-k][0]
else:
dp[i][1]+=dp[i-k][1]
print(dp[n][1]%(10**9+7))
```
| 94,750 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Quite recently a creative student Lesha had a lecture on trees. After the lecture Lesha was inspired and came up with the tree of his own which he called a k-tree.
A k-tree is an infinite rooted tree where:
* each vertex has exactly k children;
* each edge has some weight;
* if we look at the edges that goes from some vertex to its children (exactly k edges), then their weights will equal 1, 2, 3, ..., k.
The picture below shows a part of a 3-tree.
<image>
As soon as Dima, a good friend of Lesha, found out about the tree, he immediately wondered: "How many paths of total weight n (the sum of all weights of the edges in the path) are there, starting from the root of a k-tree and also containing at least one edge of weight at least d?".
Help Dima find an answer to his question. As the number of ways can be rather large, print it modulo 1000000007 (109 + 7).
Input
A single line contains three space-separated integers: n, k and d (1 ≤ n, k ≤ 100; 1 ≤ d ≤ k).
Output
Print a single integer — the answer to the problem modulo 1000000007 (109 + 7).
Examples
Input
3 3 2
Output
3
Input
3 3 3
Output
1
Input
4 3 2
Output
6
Input
4 5 2
Output
7
Tags: dp, implementation, trees
Correct Solution:
```
mod = 10**9+7
def countWays(arr, m, N,d):
count = [0 for i in range(N + 1)]
count[0] = 1
for i in range(1, N + 1):
for j in range(m):
if (i >= arr[j]) and arr[j]<d:
count[i] += count[i - arr[j]]
count[i]%=mod
return count[N]
def countWays1(arr, m, N):
count = [0 for i in range(N + 1)]
count[0] = 1
for i in range(1, N + 1):
for j in range(m):
if (i >= arr[j]):
count[i] += count[i - arr[j]]
count[i]%=mod
return count[N]
n,k,d = map(int,input().split())
a = [i for i in range(1,k+1)]
t1 = countWays(a,len(a),n,d)
t2 = countWays1(a,len(a),n)
print((t2-t1+mod)%mod)
```
| 94,751 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Quite recently a creative student Lesha had a lecture on trees. After the lecture Lesha was inspired and came up with the tree of his own which he called a k-tree.
A k-tree is an infinite rooted tree where:
* each vertex has exactly k children;
* each edge has some weight;
* if we look at the edges that goes from some vertex to its children (exactly k edges), then their weights will equal 1, 2, 3, ..., k.
The picture below shows a part of a 3-tree.
<image>
As soon as Dima, a good friend of Lesha, found out about the tree, he immediately wondered: "How many paths of total weight n (the sum of all weights of the edges in the path) are there, starting from the root of a k-tree and also containing at least one edge of weight at least d?".
Help Dima find an answer to his question. As the number of ways can be rather large, print it modulo 1000000007 (109 + 7).
Input
A single line contains three space-separated integers: n, k and d (1 ≤ n, k ≤ 100; 1 ≤ d ≤ k).
Output
Print a single integer — the answer to the problem modulo 1000000007 (109 + 7).
Examples
Input
3 3 2
Output
3
Input
3 3 3
Output
1
Input
4 3 2
Output
6
Input
4 5 2
Output
7
Tags: dp, implementation, trees
Correct Solution:
```
def dp(curr, least, k, total, loc=0):
global d
if curr == total: return int(least == 0)
if d[curr][int(least==0)] != -1: return d[curr][int(least==0)]
for i in range(1, k+1):
if curr+i > total: break
loc+= dp(curr+i, 0 if least <= i else least, k, total)
d[curr][int(least==0)] = loc % 1000000007
return loc % 1000000007
n, k, dd = map(int, input().split())
d = [[-1, -1] for i in range(n)]
print(dp(0, dd, k, n))
```
| 94,752 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Quite recently a creative student Lesha had a lecture on trees. After the lecture Lesha was inspired and came up with the tree of his own which he called a k-tree.
A k-tree is an infinite rooted tree where:
* each vertex has exactly k children;
* each edge has some weight;
* if we look at the edges that goes from some vertex to its children (exactly k edges), then their weights will equal 1, 2, 3, ..., k.
The picture below shows a part of a 3-tree.
<image>
As soon as Dima, a good friend of Lesha, found out about the tree, he immediately wondered: "How many paths of total weight n (the sum of all weights of the edges in the path) are there, starting from the root of a k-tree and also containing at least one edge of weight at least d?".
Help Dima find an answer to his question. As the number of ways can be rather large, print it modulo 1000000007 (109 + 7).
Input
A single line contains three space-separated integers: n, k and d (1 ≤ n, k ≤ 100; 1 ≤ d ≤ k).
Output
Print a single integer — the answer to the problem modulo 1000000007 (109 + 7).
Examples
Input
3 3 2
Output
3
Input
3 3 3
Output
1
Input
4 3 2
Output
6
Input
4 5 2
Output
7
Tags: dp, implementation, trees
Correct Solution:
```
mod=int(1e9+7)
n,k,d=map(int,input().split())
dp=[0 for i in range(n+k+1)]
dp[0]=1
for i in range(n+1):
for j in range(1,k+1):
dp[i+j]+=dp[i]
dp[i+j]%=mod
dp2=[0 for i in range(n+k+1)]
dp2[0]=1
for i in range(n+1):
for j in range(1,d):
dp2[i+j]+=dp2[i]
dp[i+j]%=mod
print((dp[n]-dp2[n]+mod)%mod)
```
| 94,753 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Quite recently a creative student Lesha had a lecture on trees. After the lecture Lesha was inspired and came up with the tree of his own which he called a k-tree.
A k-tree is an infinite rooted tree where:
* each vertex has exactly k children;
* each edge has some weight;
* if we look at the edges that goes from some vertex to its children (exactly k edges), then their weights will equal 1, 2, 3, ..., k.
The picture below shows a part of a 3-tree.
<image>
As soon as Dima, a good friend of Lesha, found out about the tree, he immediately wondered: "How many paths of total weight n (the sum of all weights of the edges in the path) are there, starting from the root of a k-tree and also containing at least one edge of weight at least d?".
Help Dima find an answer to his question. As the number of ways can be rather large, print it modulo 1000000007 (109 + 7).
Input
A single line contains three space-separated integers: n, k and d (1 ≤ n, k ≤ 100; 1 ≤ d ≤ k).
Output
Print a single integer — the answer to the problem modulo 1000000007 (109 + 7).
Examples
Input
3 3 2
Output
3
Input
3 3 3
Output
1
Input
4 3 2
Output
6
Input
4 5 2
Output
7
Tags: dp, implementation, trees
Correct Solution:
```
n, k, d = [int(x) for x in input().split()]
z = [[1], [1]]
for i in range(1, n + 1):
z[0].append(sum(z[0][max(i-d+1, 0):]))
z[1].append(sum(z[1][max(i-k, 0):]))
print((z[1][-1] - z[0][-1]) % (10**9+7))
```
| 94,754 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Quite recently a creative student Lesha had a lecture on trees. After the lecture Lesha was inspired and came up with the tree of his own which he called a k-tree.
A k-tree is an infinite rooted tree where:
* each vertex has exactly k children;
* each edge has some weight;
* if we look at the edges that goes from some vertex to its children (exactly k edges), then their weights will equal 1, 2, 3, ..., k.
The picture below shows a part of a 3-tree.
<image>
As soon as Dima, a good friend of Lesha, found out about the tree, he immediately wondered: "How many paths of total weight n (the sum of all weights of the edges in the path) are there, starting from the root of a k-tree and also containing at least one edge of weight at least d?".
Help Dima find an answer to his question. As the number of ways can be rather large, print it modulo 1000000007 (109 + 7).
Input
A single line contains three space-separated integers: n, k and d (1 ≤ n, k ≤ 100; 1 ≤ d ≤ k).
Output
Print a single integer — the answer to the problem modulo 1000000007 (109 + 7).
Examples
Input
3 3 2
Output
3
Input
3 3 3
Output
1
Input
4 3 2
Output
6
Input
4 5 2
Output
7
Tags: dp, implementation, trees
Correct Solution:
```
N,K,D=map(int,input().split())
mod=10**9+7
dpK=[0 for i in range(N+1)]
dpK[0]=1
for i in range(1,N+1):
for j in range(1,K+1):
if i>=j:
dpK[i]+=dpK[i-j]
dpK[i]%=mod
dp=[0 for i in range(N+1)]
dp[0]=1
for i in range(1,N+1):
for j in range(1,D):
if i>=j:
dp[i]+=dp[i-j]
dp[i]%=mod
ans=dpK[N]-dp[N]
print(ans%mod)
```
| 94,755 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Quite recently a creative student Lesha had a lecture on trees. After the lecture Lesha was inspired and came up with the tree of his own which he called a k-tree.
A k-tree is an infinite rooted tree where:
* each vertex has exactly k children;
* each edge has some weight;
* if we look at the edges that goes from some vertex to its children (exactly k edges), then their weights will equal 1, 2, 3, ..., k.
The picture below shows a part of a 3-tree.
<image>
As soon as Dima, a good friend of Lesha, found out about the tree, he immediately wondered: "How many paths of total weight n (the sum of all weights of the edges in the path) are there, starting from the root of a k-tree and also containing at least one edge of weight at least d?".
Help Dima find an answer to his question. As the number of ways can be rather large, print it modulo 1000000007 (109 + 7).
Input
A single line contains three space-separated integers: n, k and d (1 ≤ n, k ≤ 100; 1 ≤ d ≤ k).
Output
Print a single integer — the answer to the problem modulo 1000000007 (109 + 7).
Examples
Input
3 3 2
Output
3
Input
3 3 3
Output
1
Input
4 3 2
Output
6
Input
4 5 2
Output
7
Tags: dp, implementation, trees
Correct Solution:
```
n, k, d = map(int, input().split())
dp = [[0 for i in range(2)] for j in range(n + 10)]
dp[0][0] = 1
MOD = int(1e9) + 7
for i in range(1, n + 1):
for j in range(1, min(d - 1, n) + 1):
dp[i][0] += dp[i - j][0] % MOD
for j in range(1, min(d - 1, n) + 1):
dp[i][1] += dp[i - j][1] % MOD
for j in range(d, min(n, k) + 1):
dp[i][1] += (dp[i - j][0] + dp[i - j][1]) % MOD
print(dp[n][1] % MOD)
```
| 94,756 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Quite recently a creative student Lesha had a lecture on trees. After the lecture Lesha was inspired and came up with the tree of his own which he called a k-tree.
A k-tree is an infinite rooted tree where:
* each vertex has exactly k children;
* each edge has some weight;
* if we look at the edges that goes from some vertex to its children (exactly k edges), then their weights will equal 1, 2, 3, ..., k.
The picture below shows a part of a 3-tree.
<image>
As soon as Dima, a good friend of Lesha, found out about the tree, he immediately wondered: "How many paths of total weight n (the sum of all weights of the edges in the path) are there, starting from the root of a k-tree and also containing at least one edge of weight at least d?".
Help Dima find an answer to his question. As the number of ways can be rather large, print it modulo 1000000007 (109 + 7).
Input
A single line contains three space-separated integers: n, k and d (1 ≤ n, k ≤ 100; 1 ≤ d ≤ k).
Output
Print a single integer — the answer to the problem modulo 1000000007 (109 + 7).
Examples
Input
3 3 2
Output
3
Input
3 3 3
Output
1
Input
4 3 2
Output
6
Input
4 5 2
Output
7
Tags: dp, implementation, trees
Correct Solution:
```
import sys
from math import log2,floor,ceil,sqrt,gcd
# import bisect
# from collections import deque
# sys.setrecursionlimit(7*10**4)
Ri = lambda : [int(x) for x in sys.stdin.readline().split()]
ri = lambda : sys.stdin.readline().strip()
def input(): return sys.stdin.readline().strip()
def list2d(a, b, c): return [[c] * b for i in range(a)]
def list3d(a, b, c, d): return [[[d] * c for j in range(b)] for i in range(a)]
def list4d(a, b, c, d, e): return [[[[e] * d for j in range(c)] for j in range(b)] for i in range(a)]
def ceil(x, y=1): return int(-(-x // y))
def INT(): return int(input())
def MAP(): return map(int, input().split())
def LIST(N=None): return list(MAP()) if N is None else [INT() for i in range(N)]
def Yes(): print('Yes')
def No(): print('No')
def YES(): print('YES')
def NO(): print('NO')
INF = 10 ** 18
MOD = 1000000007
n,k,d = Ri()
no = [0]*(n+1)
no[0] = 1
for i in range(1,n+1):
for j in range(1,k+1):
if j > i:
break
no[i]+=no[i-j]
# no[i] = no[i]%MOD
# print(no)
nod = [0]*(n+1)
nod[0] = 1
for i in range(1,n+1):
for j in range(1,k+1):
if j > i : break
if j >= d : break
nod[i]+=nod[i-j]
# nod[i]%=MOD
# print(nod)
print((no[n]-nod[n])%MOD)
```
| 94,757 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Quite recently a creative student Lesha had a lecture on trees. After the lecture Lesha was inspired and came up with the tree of his own which he called a k-tree.
A k-tree is an infinite rooted tree where:
* each vertex has exactly k children;
* each edge has some weight;
* if we look at the edges that goes from some vertex to its children (exactly k edges), then their weights will equal 1, 2, 3, ..., k.
The picture below shows a part of a 3-tree.
<image>
As soon as Dima, a good friend of Lesha, found out about the tree, he immediately wondered: "How many paths of total weight n (the sum of all weights of the edges in the path) are there, starting from the root of a k-tree and also containing at least one edge of weight at least d?".
Help Dima find an answer to his question. As the number of ways can be rather large, print it modulo 1000000007 (109 + 7).
Input
A single line contains three space-separated integers: n, k and d (1 ≤ n, k ≤ 100; 1 ≤ d ≤ k).
Output
Print a single integer — the answer to the problem modulo 1000000007 (109 + 7).
Examples
Input
3 3 2
Output
3
Input
3 3 3
Output
1
Input
4 3 2
Output
6
Input
4 5 2
Output
7
Submitted Solution:
```
import sys, os, io
def rs(): return sys.stdin.readline().rstrip()
def ri(): return int(sys.stdin.readline())
def ria(): return list(map(int, sys.stdin.readline().split()))
def ws(s): sys.stdout.write(s + '\n')
def wi(n): sys.stdout.write(str(n) + '\n')
def wia(a): sys.stdout.write(' '.join([str(x) for x in a]) + '\n')
import math,datetime,functools,itertools,operator,bisect,fractions,statistics
from collections import deque,defaultdict,OrderedDict,Counter
from fractions import Fraction
from decimal import Decimal
from sys import stdout
from heapq import heappush, heappop, heapify ,_heapify_max,_heappop_max,nsmallest,nlargest
sys.setrecursionlimit(111111)
INF=999999999999999999999999
class SortedList:
def __init__(self, iterable=[], _load=200):
"""Initialize sorted list instance."""
values = sorted(iterable)
self._len = _len = len(values)
self._load = _load
self._lists = _lists = [values[i:i + _load] for i in range(0, _len, _load)]
self._list_lens = [len(_list) for _list in _lists]
self._mins = [_list[0] for _list in _lists]
self._fen_tree = []
self._rebuild = True
def _fen_build(self):
"""Build a fenwick tree instance."""
self._fen_tree[:] = self._list_lens
_fen_tree = self._fen_tree
for i in range(len(_fen_tree)):
if i | i + 1 < len(_fen_tree):
_fen_tree[i | i + 1] += _fen_tree[i]
self._rebuild = False
def _fen_update(self, index, value):
"""Update `fen_tree[index] += value`."""
if not self._rebuild:
_fen_tree = self._fen_tree
while index < len(_fen_tree):
_fen_tree[index] += value
index |= index + 1
def _fen_query(self, end):
"""Return `sum(_fen_tree[:end])`."""
if self._rebuild:
self._fen_build()
_fen_tree = self._fen_tree
x = 0
while end:
x += _fen_tree[end - 1]
end &= end - 1
return x
def _fen_findkth(self, k):
"""Return a pair of (the largest `idx` such that `sum(_fen_tree[:idx]) <= k`, `k - sum(_fen_tree[:idx])`)."""
_list_lens = self._list_lens
if k < _list_lens[0]:
return 0, k
if k >= self._len - _list_lens[-1]:
return len(_list_lens) - 1, k + _list_lens[-1] - self._len
if self._rebuild:
self._fen_build()
_fen_tree = self._fen_tree
idx = -1
for d in reversed(range(len(_fen_tree).bit_length())):
right_idx = idx + (1 << d)
if right_idx < len(_fen_tree) and k >= _fen_tree[right_idx]:
idx = right_idx
k -= _fen_tree[idx]
return idx + 1, k
def _delete(self, pos, idx):
"""Delete value at the given `(pos, idx)`."""
_lists = self._lists
_mins = self._mins
_list_lens = self._list_lens
self._len -= 1
self._fen_update(pos, -1)
del _lists[pos][idx]
_list_lens[pos] -= 1
if _list_lens[pos]:
_mins[pos] = _lists[pos][0]
else:
del _lists[pos]
del _list_lens[pos]
del _mins[pos]
self._rebuild = True
def _loc_left(self, value):
"""Return an index pair that corresponds to the first position of `value` in the sorted list."""
if not self._len:
return 0, 0
_lists = self._lists
_mins = self._mins
lo, pos = -1, len(_lists) - 1
while lo + 1 < pos:
mi = (lo + pos) >> 1
if value <= _mins[mi]:
pos = mi
else:
lo = mi
if pos and value <= _lists[pos - 1][-1]:
pos -= 1
_list = _lists[pos]
lo, idx = -1, len(_list)
while lo + 1 < idx:
mi = (lo + idx) >> 1
if value <= _list[mi]:
idx = mi
else:
lo = mi
return pos, idx
def _loc_right(self, value):
"""Return an index pair that corresponds to the last position of `value` in the sorted list."""
if not self._len:
return 0, 0
_lists = self._lists
_mins = self._mins
pos, hi = 0, len(_lists)
while pos + 1 < hi:
mi = (pos + hi) >> 1
if value < _mins[mi]:
hi = mi
else:
pos = mi
_list = _lists[pos]
lo, idx = -1, len(_list)
while lo + 1 < idx:
mi = (lo + idx) >> 1
if value < _list[mi]:
idx = mi
else:
lo = mi
return pos, idx
def add(self, value):
"""Add `value` to sorted list."""
_load = self._load
_lists = self._lists
_mins = self._mins
_list_lens = self._list_lens
self._len += 1
if _lists:
pos, idx = self._loc_right(value)
self._fen_update(pos, 1)
_list = _lists[pos]
_list.insert(idx, value)
_list_lens[pos] += 1
_mins[pos] = _list[0]
if _load + _load < len(_list):
_lists.insert(pos + 1, _list[_load:])
_list_lens.insert(pos + 1, len(_list) - _load)
_mins.insert(pos + 1, _list[_load])
_list_lens[pos] = _load
del _list[_load:]
self._rebuild = True
else:
_lists.append([value])
_mins.append(value)
_list_lens.append(1)
self._rebuild = True
def discard(self, value):
"""Remove `value` from sorted list if it is a member."""
_lists = self._lists
if _lists:
pos, idx = self._loc_right(value)
if idx and _lists[pos][idx - 1] == value:
self._delete(pos, idx - 1)
def remove(self, value):
"""Remove `value` from sorted list; `value` must be a member."""
_len = self._len
self.discard(value)
if _len == self._len:
raise ValueError('{0!r} not in list'.format(value))
def pop(self, index=-1):
"""Remove and return value at `index` in sorted list."""
pos, idx = self._fen_findkth(self._len + index if index < 0 else index)
value = self._lists[pos][idx]
self._delete(pos, idx)
return value
def bisect_left(self, value):
"""Return the first index to insert `value` in the sorted list."""
pos, idx = self._loc_left(value)
return self._fen_query(pos) + idx
def bisect_right(self, value):
"""Return the last index to insert `value` in the sorted list."""
pos, idx = self._loc_right(value)
return self._fen_query(pos) + idx
def count(self, value):
"""Return number of occurrences of `value` in the sorted list."""
return self.bisect_right(value) - self.bisect_left(value)
def __len__(self):
"""Return the size of the sorted list."""
return self._len
def __getitem__(self, index):
"""Lookup value at `index` in sorted list."""
pos, idx = self._fen_findkth(self._len + index if index < 0 else index)
return self._lists[pos][idx]
def __delitem__(self, index):
"""Remove value at `index` from sorted list."""
pos, idx = self._fen_findkth(self._len + index if index < 0 else index)
self._delete(pos, idx)
def __contains__(self, value):
"""Return true if `value` is an element of the sorted list."""
_lists = self._lists
if _lists:
pos, idx = self._loc_left(value)
return idx < len(_lists[pos]) and _lists[pos][idx] == value
return False
def __iter__(self):
"""Return an iterator over the sorted list."""
return (value for _list in self._lists for value in _list)
def __reversed__(self):
"""Return a reverse iterator over the sorted list."""
return (value for _list in reversed(self._lists) for value in reversed(_list))
def __repr__(self):
"""Return string representation of sorted list."""
return 'SortedList({0})'.format(list(self))
def main():
mod=1000000007
# InverseofNumber(mod)
# InverseofFactorial(mod)
# factorial(mod)
starttime=datetime.datetime.now()
if(os.path.exists('input.txt')):
sys.stdin = open("input.txt","r")
sys.stdout = open("output.txt","w")
###CODE
tc = 1
for _ in range(tc):
n,k,d=ria()
coins=[int(x) for x in range(1,k+1)]
x=n
dp=[0]*1000005
dp[0]=1
mod=int(1e9)+7
for i in range(1,x+1):
for j in coins:
if j-i>0:
break
dp[i]=(dp[i]+dp[i-j])%mod
total=(dp[x])
coins=[int(x) for x in range(1,d)]
x=n
dp=[0]*1000005
dp[0]=1
mod=int(1e9)+7
for i in range(1,x+1):
for j in coins:
if j-i>0:
break
dp[i]=(dp[i]+dp[i-j])%mod
waste=dp[x]
print((total-waste)%mod)
#<--Solving Area Ends
endtime=datetime.datetime.now()
time=(endtime-starttime).total_seconds()*1000
if(os.path.exists('input.txt')):
print("Time:",time,"ms")
class FastReader(io.IOBase):
newlines = 0
def __init__(self, fd, chunk_size=1024 * 8):
self._fd = fd
self._chunk_size = chunk_size
self.buffer = io.BytesIO()
def read(self):
while True:
b = os.read(self._fd, max(os.fstat(self._fd).st_size, self._chunk_size))
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, size=-1):
while self.newlines == 0:
b = os.read(self._fd, max(os.fstat(self._fd).st_size, self._chunk_size if size == -1 else size))
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()
class FastWriter(io.IOBase):
def __init__(self, fd):
self._fd = fd
self.buffer = io.BytesIO()
self.write = self.buffer.write
def flush(self):
os.write(self._fd, self.buffer.getvalue())
self.buffer.truncate(0), self.buffer.seek(0)
class FastStdin(io.IOBase):
def __init__(self, fd=0):
self.buffer = FastReader(fd)
self.read = lambda: self.buffer.read().decode("ascii")
self.readline = lambda: self.buffer.readline().decode("ascii")
class FastStdout(io.IOBase):
def __init__(self, fd=1):
self.buffer = FastWriter(fd)
self.write = lambda s: self.buffer.write(s.encode("ascii"))
self.flush = self.buffer.flush
if __name__ == '__main__':
sys.stdin = FastStdin()
sys.stdout = FastStdout()
main()
```
Yes
| 94,758 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Quite recently a creative student Lesha had a lecture on trees. After the lecture Lesha was inspired and came up with the tree of his own which he called a k-tree.
A k-tree is an infinite rooted tree where:
* each vertex has exactly k children;
* each edge has some weight;
* if we look at the edges that goes from some vertex to its children (exactly k edges), then their weights will equal 1, 2, 3, ..., k.
The picture below shows a part of a 3-tree.
<image>
As soon as Dima, a good friend of Lesha, found out about the tree, he immediately wondered: "How many paths of total weight n (the sum of all weights of the edges in the path) are there, starting from the root of a k-tree and also containing at least one edge of weight at least d?".
Help Dima find an answer to his question. As the number of ways can be rather large, print it modulo 1000000007 (109 + 7).
Input
A single line contains three space-separated integers: n, k and d (1 ≤ n, k ≤ 100; 1 ≤ d ≤ k).
Output
Print a single integer — the answer to the problem modulo 1000000007 (109 + 7).
Examples
Input
3 3 2
Output
3
Input
3 3 3
Output
1
Input
4 3 2
Output
6
Input
4 5 2
Output
7
Submitted Solution:
```
#!/usr/bin/env python3
import itertools, functools, math
MOD = 1000000007
@functools.lru_cache(None)
def dp(n, k, d, d_used=False):
if n == d and not d_used:
return 1
if n == 0:
return 1
if n < d and not d_used:
return 0
r = 0
for i in range(1, min(n+1, k+1)):
r = (r + dp(n-i, k, d, d_used or i>=d))%MOD
return r
def solve():
n, k, d = map(int, input().split())
return dp(n, k, d)
if __name__ == '__main__':
print(solve())
```
Yes
| 94,759 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Quite recently a creative student Lesha had a lecture on trees. After the lecture Lesha was inspired and came up with the tree of his own which he called a k-tree.
A k-tree is an infinite rooted tree where:
* each vertex has exactly k children;
* each edge has some weight;
* if we look at the edges that goes from some vertex to its children (exactly k edges), then their weights will equal 1, 2, 3, ..., k.
The picture below shows a part of a 3-tree.
<image>
As soon as Dima, a good friend of Lesha, found out about the tree, he immediately wondered: "How many paths of total weight n (the sum of all weights of the edges in the path) are there, starting from the root of a k-tree and also containing at least one edge of weight at least d?".
Help Dima find an answer to his question. As the number of ways can be rather large, print it modulo 1000000007 (109 + 7).
Input
A single line contains three space-separated integers: n, k and d (1 ≤ n, k ≤ 100; 1 ≤ d ≤ k).
Output
Print a single integer — the answer to the problem modulo 1000000007 (109 + 7).
Examples
Input
3 3 2
Output
3
Input
3 3 3
Output
1
Input
4 3 2
Output
6
Input
4 5 2
Output
7
Submitted Solution:
```
import functools
import sys
p = 10**9 + 7
line = input()
tokens = line.split()
n, k, d = int(tokens[0]), int(tokens[1]), int(tokens[2])
@functools.lru_cache(None)
def f(s):
if s == 0:
return 1
total = 0
for w in range(1, k + 1):
if w > s:
break
total += f(s - w)
return total % p
@functools.lru_cache(None)
def g(s):
if s == 0:
return 1
total = 0
for w in range(1, min(d, k + 1)):
if w > s:
break
total += g(s - w)
return total % p
print((f(n) - g(n)) % p)
```
Yes
| 94,760 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Quite recently a creative student Lesha had a lecture on trees. After the lecture Lesha was inspired and came up with the tree of his own which he called a k-tree.
A k-tree is an infinite rooted tree where:
* each vertex has exactly k children;
* each edge has some weight;
* if we look at the edges that goes from some vertex to its children (exactly k edges), then their weights will equal 1, 2, 3, ..., k.
The picture below shows a part of a 3-tree.
<image>
As soon as Dima, a good friend of Lesha, found out about the tree, he immediately wondered: "How many paths of total weight n (the sum of all weights of the edges in the path) are there, starting from the root of a k-tree and also containing at least one edge of weight at least d?".
Help Dima find an answer to his question. As the number of ways can be rather large, print it modulo 1000000007 (109 + 7).
Input
A single line contains three space-separated integers: n, k and d (1 ≤ n, k ≤ 100; 1 ≤ d ≤ k).
Output
Print a single integer — the answer to the problem modulo 1000000007 (109 + 7).
Examples
Input
3 3 2
Output
3
Input
3 3 3
Output
1
Input
4 3 2
Output
6
Input
4 5 2
Output
7
Submitted Solution:
```
n, k, d = list(map(int, input().split()))
MOD = 10 ** 9 + 7
dp = {}
def rec(remaining, flag = False):
if remaining < 0:
return 0
if remaining == 0 and flag == True:
return 1
if (remaining, flag) in dp:
return dp[(remaining, flag)]
ans = 0
for i in range(1,k+1):
if i <= remaining:
ans += rec(remaining - i, flag | (i>=d))
ans %= MOD
dp[(remaining, flag)] = ans
return ans
ans = rec(n) % MOD
print(ans)
```
Yes
| 94,761 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Quite recently a creative student Lesha had a lecture on trees. After the lecture Lesha was inspired and came up with the tree of his own which he called a k-tree.
A k-tree is an infinite rooted tree where:
* each vertex has exactly k children;
* each edge has some weight;
* if we look at the edges that goes from some vertex to its children (exactly k edges), then their weights will equal 1, 2, 3, ..., k.
The picture below shows a part of a 3-tree.
<image>
As soon as Dima, a good friend of Lesha, found out about the tree, he immediately wondered: "How many paths of total weight n (the sum of all weights of the edges in the path) are there, starting from the root of a k-tree and also containing at least one edge of weight at least d?".
Help Dima find an answer to his question. As the number of ways can be rather large, print it modulo 1000000007 (109 + 7).
Input
A single line contains three space-separated integers: n, k and d (1 ≤ n, k ≤ 100; 1 ≤ d ≤ k).
Output
Print a single integer — the answer to the problem modulo 1000000007 (109 + 7).
Examples
Input
3 3 2
Output
3
Input
3 3 3
Output
1
Input
4 3 2
Output
6
Input
4 5 2
Output
7
Submitted Solution:
```
memo = {}
tg,k,d = map(int,input().split())
def rec(n):
if n in memo:
return memo[n]
ans = [0,0]
for b in range(1, min(k,n)+1):
if b == n:
ans[b>=d]+=1
continue
r = rec(n-b)
ans[1]+=r[1]
ans[b>=d]+=r[0]
memo[n] = ans
return ans
print(rec(tg)[1])
```
No
| 94,762 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Quite recently a creative student Lesha had a lecture on trees. After the lecture Lesha was inspired and came up with the tree of his own which he called a k-tree.
A k-tree is an infinite rooted tree where:
* each vertex has exactly k children;
* each edge has some weight;
* if we look at the edges that goes from some vertex to its children (exactly k edges), then their weights will equal 1, 2, 3, ..., k.
The picture below shows a part of a 3-tree.
<image>
As soon as Dima, a good friend of Lesha, found out about the tree, he immediately wondered: "How many paths of total weight n (the sum of all weights of the edges in the path) are there, starting from the root of a k-tree and also containing at least one edge of weight at least d?".
Help Dima find an answer to his question. As the number of ways can be rather large, print it modulo 1000000007 (109 + 7).
Input
A single line contains three space-separated integers: n, k and d (1 ≤ n, k ≤ 100; 1 ≤ d ≤ k).
Output
Print a single integer — the answer to the problem modulo 1000000007 (109 + 7).
Examples
Input
3 3 2
Output
3
Input
3 3 3
Output
1
Input
4 3 2
Output
6
Input
4 5 2
Output
7
Submitted Solution:
```
import sys
sys.setrecursionlimit(100000)
n, k, d = [int(x) for x in sys.stdin.readline().strip().split()]
memo = {}
m = 10**9 +7
def dp(n,k,d):
if n in memo:
return memo[n]
if n==0:
return 1
if n<0:
return 0
s = 0
for i in range(1,k+1):
if i>=d :
s+=dp(n-i,k,0)
elif n-i>=d:
s+=dp(n-i,k,d)
memo[n]=s
return s
print(dp(n,k,d)%m)
```
No
| 94,763 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Quite recently a creative student Lesha had a lecture on trees. After the lecture Lesha was inspired and came up with the tree of his own which he called a k-tree.
A k-tree is an infinite rooted tree where:
* each vertex has exactly k children;
* each edge has some weight;
* if we look at the edges that goes from some vertex to its children (exactly k edges), then their weights will equal 1, 2, 3, ..., k.
The picture below shows a part of a 3-tree.
<image>
As soon as Dima, a good friend of Lesha, found out about the tree, he immediately wondered: "How many paths of total weight n (the sum of all weights of the edges in the path) are there, starting from the root of a k-tree and also containing at least one edge of weight at least d?".
Help Dima find an answer to his question. As the number of ways can be rather large, print it modulo 1000000007 (109 + 7).
Input
A single line contains three space-separated integers: n, k and d (1 ≤ n, k ≤ 100; 1 ≤ d ≤ k).
Output
Print a single integer — the answer to the problem modulo 1000000007 (109 + 7).
Examples
Input
3 3 2
Output
3
Input
3 3 3
Output
1
Input
4 3 2
Output
6
Input
4 5 2
Output
7
Submitted Solution:
```
import sys
from functools import lru_cache, cmp_to_key
from heapq import merge, heapify, heappop, heappush
# from math import *
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
from time import perf_counter
from fractions import Fraction
import copy
import time
# import numpy as np
starttime = time.time()
# import numpy as np
mod = int(pow(10, 9) + 7)
mod2 = 998244353
def data(): return sys.stdin.readline().strip()
def out(*var, end="\n"): sys.stdout.write(' '.join(map(str, var))+end)
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 [l1d(n, val) for j in range(m)]
try:
# sys.setrecursionlimit(int(pow(10,6)))
sys.stdin = open("input.txt", "r")
# sys.stdout = open("../output.txt", "w")
except:
pass
n,k,d=L()
def func(n,A):
@lru_cache
def rec(s):
# print(s)
if s==0:
return 1
if s<0:
return 0
ans=0
for x in A:
ans+=rec(s-x)
ans%=mod
return ans
return rec(n)
ans=func(n,[i for i in range(1,k+1)])
if d!=1:
ans-=func(n,[i for i in range(1,d)])
print(ans)
endtime = time.time()
# print(f"Runtime of the program is {endtime - starttime}")
```
No
| 94,764 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Quite recently a creative student Lesha had a lecture on trees. After the lecture Lesha was inspired and came up with the tree of his own which he called a k-tree.
A k-tree is an infinite rooted tree where:
* each vertex has exactly k children;
* each edge has some weight;
* if we look at the edges that goes from some vertex to its children (exactly k edges), then their weights will equal 1, 2, 3, ..., k.
The picture below shows a part of a 3-tree.
<image>
As soon as Dima, a good friend of Lesha, found out about the tree, he immediately wondered: "How many paths of total weight n (the sum of all weights of the edges in the path) are there, starting from the root of a k-tree and also containing at least one edge of weight at least d?".
Help Dima find an answer to his question. As the number of ways can be rather large, print it modulo 1000000007 (109 + 7).
Input
A single line contains three space-separated integers: n, k and d (1 ≤ n, k ≤ 100; 1 ≤ d ≤ k).
Output
Print a single integer — the answer to the problem modulo 1000000007 (109 + 7).
Examples
Input
3 3 2
Output
3
Input
3 3 3
Output
1
Input
4 3 2
Output
6
Input
4 5 2
Output
7
Submitted Solution:
```
n,k,d=map(int,input().split(" "))
dp=[[0,0] for i in range(n+1)]
dp[0][0]=1
for i in range(1,n+1):
for j in range(1,k+1):
if(i-j<0):
break
if(j<d):
dp[i][0]+=dp[i-j][0]%1000000007
dp[i][1]+=dp[i-j][1]%1000000007
else:
dp[i][1]+=dp[i-j][0]%1000000007
dp[i][1]+=dp[i-j][1]%1000000007
print(dp[n][1])
```
No
| 94,765 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Lord Tirek is a centaur and the main antagonist in the season four finale episodes in the series "My Little Pony: Friendship Is Magic". In "Twilight's Kingdom" (Part 1), Tirek escapes from Tartarus and drains magic from ponies to grow stronger.
<image>
The core skill of Tirek is called Absorb Mana. It takes all mana from a magic creature and gives them to the caster.
Now to simplify the problem, assume you have n ponies (numbered from 1 to n). Each pony has three attributes:
* si : amount of mana that the pony has at time 0;
* mi : maximum mana that the pony can have;
* ri : mana regeneration per unit time.
Lord Tirek will do m instructions, each of them can be described with three integers: ti, li, ri. The instruction means that at time ti, Tirek will use Absorb Mana on ponies with numbers from li to ri (both borders inclusive). We'll give you all the m instructions in order, count how much mana Tirek absorbs for each instruction.
Input
The first line contains an integer n (1 ≤ n ≤ 105) — the number of ponies. Each of the next n lines contains three integers si, mi, ri (0 ≤ si ≤ mi ≤ 105; 0 ≤ ri ≤ 105), describing a pony.
The next line contains an integer m (1 ≤ m ≤ 105) — the number of instructions. Each of the next m lines contains three integers ti, li, ri (0 ≤ ti ≤ 109; 1 ≤ li ≤ ri ≤ n), describing an instruction of Lord Tirek. The instructions are given in strictly increasing order of ti (all ti are distinct).
Output
For each instruction, output a single line which contains a single integer, the total mana absorbed in this instruction.
Examples
Input
5
0 10 1
0 12 1
0 20 1
0 12 1
0 10 1
2
5 1 5
19 1 5
Output
25
58
Note
Every pony starts with zero mana. For the first instruction, each pony has 5 mana, so you get 25 mana in total and each pony has 0 mana after the first instruction.
For the second instruction, pony 3 has 14 mana and other ponies have mana equal to their mi.
Submitted Solution:
```
pony_count = int(input())
ponies = []
for _ in range(pony_count):
ponies.append([int(i) for i in input().split()])
instruction_count = int(input())
earlierTime = 0
for _ in range(instruction_count):
time,x,y = [int(i) for i in input().split()]
mana_absorbed = 0
for i in range(x-1,y):
amount = min(ponies[i][2]*(time-earlierTime)+ponies[i][0],ponies[i][1])
mana_absorbed+=amount
ponies[i][0]=0
earlierTime=time
print(mana_absorbed)
```
No
| 94,766 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Lord Tirek is a centaur and the main antagonist in the season four finale episodes in the series "My Little Pony: Friendship Is Magic". In "Twilight's Kingdom" (Part 1), Tirek escapes from Tartarus and drains magic from ponies to grow stronger.
<image>
The core skill of Tirek is called Absorb Mana. It takes all mana from a magic creature and gives them to the caster.
Now to simplify the problem, assume you have n ponies (numbered from 1 to n). Each pony has three attributes:
* si : amount of mana that the pony has at time 0;
* mi : maximum mana that the pony can have;
* ri : mana regeneration per unit time.
Lord Tirek will do m instructions, each of them can be described with three integers: ti, li, ri. The instruction means that at time ti, Tirek will use Absorb Mana on ponies with numbers from li to ri (both borders inclusive). We'll give you all the m instructions in order, count how much mana Tirek absorbs for each instruction.
Input
The first line contains an integer n (1 ≤ n ≤ 105) — the number of ponies. Each of the next n lines contains three integers si, mi, ri (0 ≤ si ≤ mi ≤ 105; 0 ≤ ri ≤ 105), describing a pony.
The next line contains an integer m (1 ≤ m ≤ 105) — the number of instructions. Each of the next m lines contains three integers ti, li, ri (0 ≤ ti ≤ 109; 1 ≤ li ≤ ri ≤ n), describing an instruction of Lord Tirek. The instructions are given in strictly increasing order of ti (all ti are distinct).
Output
For each instruction, output a single line which contains a single integer, the total mana absorbed in this instruction.
Examples
Input
5
0 10 1
0 12 1
0 20 1
0 12 1
0 10 1
2
5 1 5
19 1 5
Output
25
58
Note
Every pony starts with zero mana. For the first instruction, each pony has 5 mana, so you get 25 mana in total and each pony has 0 mana after the first instruction.
For the second instruction, pony 3 has 14 mana and other ponies have mana equal to their mi.
Submitted Solution:
```
pony_count = int(input())
ponies = []
for _ in range(pony_count):
ponies.append([int(i) for i in input().split()])
instruction_count = int(input())
earlierTime = 0
for _ in range(instruction_count):
time,x,y = [int(i) for i in input().split()]
mana_absorbed = 0
for i in range(x-1,y):
amount = min(ponies[i][2]*(time-earlierTime),ponies[i][1])-ponies[i][0]
mana_absorbed+=amount
earlierTime=time
print(mana_absorbed)
```
No
| 94,767 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Dreamoon loves summing up something for no reason. One day he obtains two integers a and b occasionally. He wants to calculate the sum of all nice integers. Positive integer x is called nice if <image> and <image>, where k is some integer number in range [1, a].
By <image> we denote the quotient of integer division of x and y. By <image> we denote the remainder of integer division of x and y. You can read more about these operations here: http://goo.gl/AcsXhT.
The answer may be large, so please print its remainder modulo 1 000 000 007 (109 + 7). Can you compute it faster than Dreamoon?
Input
The single line of the input contains two integers a, b (1 ≤ a, b ≤ 107).
Output
Print a single integer representing the answer modulo 1 000 000 007 (109 + 7).
Examples
Input
1 1
Output
0
Input
2 2
Output
8
Note
For the first sample, there are no nice integers because <image> is always zero.
For the second sample, the set of nice integers is {3, 5}.
Tags: math
Correct Solution:
```
a,b=map(int, input().split())
m=1000000007
B = int((b*(b-1)/2) % m );
A1 = int((a*(a+1)/2) % m );
A = int((A1*b+a) % m );
res = int((A*B) % m) ;
print(res)
```
| 94,768 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Dreamoon loves summing up something for no reason. One day he obtains two integers a and b occasionally. He wants to calculate the sum of all nice integers. Positive integer x is called nice if <image> and <image>, where k is some integer number in range [1, a].
By <image> we denote the quotient of integer division of x and y. By <image> we denote the remainder of integer division of x and y. You can read more about these operations here: http://goo.gl/AcsXhT.
The answer may be large, so please print its remainder modulo 1 000 000 007 (109 + 7). Can you compute it faster than Dreamoon?
Input
The single line of the input contains two integers a, b (1 ≤ a, b ≤ 107).
Output
Print a single integer representing the answer modulo 1 000 000 007 (109 + 7).
Examples
Input
1 1
Output
0
Input
2 2
Output
8
Note
For the first sample, there are no nice integers because <image> is always zero.
For the second sample, the set of nice integers is {3, 5}.
Tags: math
Correct Solution:
```
a,b = map(int,input().split())
MOD = 1000000007
x = a*(a + 1)
x = x // 2
x = x % MOD
x = (x * b) % MOD
x = (x + a) % MOD
x = ((x*b*(b - 1)) // 2) % MOD
print(x)
```
| 94,769 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Dreamoon loves summing up something for no reason. One day he obtains two integers a and b occasionally. He wants to calculate the sum of all nice integers. Positive integer x is called nice if <image> and <image>, where k is some integer number in range [1, a].
By <image> we denote the quotient of integer division of x and y. By <image> we denote the remainder of integer division of x and y. You can read more about these operations here: http://goo.gl/AcsXhT.
The answer may be large, so please print its remainder modulo 1 000 000 007 (109 + 7). Can you compute it faster than Dreamoon?
Input
The single line of the input contains two integers a, b (1 ≤ a, b ≤ 107).
Output
Print a single integer representing the answer modulo 1 000 000 007 (109 + 7).
Examples
Input
1 1
Output
0
Input
2 2
Output
8
Note
For the first sample, there are no nice integers because <image> is always zero.
For the second sample, the set of nice integers is {3, 5}.
Tags: math
Correct Solution:
```
a,b=map(int,input().split())
h=1000000007
c=((a*(b*b-b))//2)%h;
d=((a*a+a)//2)%h;
e=((b*b*b-b*b)//2)%h;
print((c+(d*e)%h)%h)
```
| 94,770 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Dreamoon loves summing up something for no reason. One day he obtains two integers a and b occasionally. He wants to calculate the sum of all nice integers. Positive integer x is called nice if <image> and <image>, where k is some integer number in range [1, a].
By <image> we denote the quotient of integer division of x and y. By <image> we denote the remainder of integer division of x and y. You can read more about these operations here: http://goo.gl/AcsXhT.
The answer may be large, so please print its remainder modulo 1 000 000 007 (109 + 7). Can you compute it faster than Dreamoon?
Input
The single line of the input contains two integers a, b (1 ≤ a, b ≤ 107).
Output
Print a single integer representing the answer modulo 1 000 000 007 (109 + 7).
Examples
Input
1 1
Output
0
Input
2 2
Output
8
Note
For the first sample, there are no nice integers because <image> is always zero.
For the second sample, the set of nice integers is {3, 5}.
Tags: math
Correct Solution:
```
# -*- coding: utf-8 -*-
"""
Created on Wed Jul 7 23:26:09 2021
@author: Kevin Chang
Project: Codeforces Problem 476C
"""
a, b = list(map(int, input().split()))
modu = 10**9+7
res = (b*(b-1)//2)*((b*a*(a+1)//2)+a)%modu
print(res)
```
| 94,771 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Dreamoon loves summing up something for no reason. One day he obtains two integers a and b occasionally. He wants to calculate the sum of all nice integers. Positive integer x is called nice if <image> and <image>, where k is some integer number in range [1, a].
By <image> we denote the quotient of integer division of x and y. By <image> we denote the remainder of integer division of x and y. You can read more about these operations here: http://goo.gl/AcsXhT.
The answer may be large, so please print its remainder modulo 1 000 000 007 (109 + 7). Can you compute it faster than Dreamoon?
Input
The single line of the input contains two integers a, b (1 ≤ a, b ≤ 107).
Output
Print a single integer representing the answer modulo 1 000 000 007 (109 + 7).
Examples
Input
1 1
Output
0
Input
2 2
Output
8
Note
For the first sample, there are no nice integers because <image> is always zero.
For the second sample, the set of nice integers is {3, 5}.
Tags: math
Correct Solution:
```
mod =10**9+7
a,b = map(int,input().split())
t1 = (b*(b-1)//2)%mod
t2 = (a*(a+1)//2)%mod
t3= (t2*b)%mod +a
ans = (t1 * t3)%mod
print(ans)
```
| 94,772 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Dreamoon loves summing up something for no reason. One day he obtains two integers a and b occasionally. He wants to calculate the sum of all nice integers. Positive integer x is called nice if <image> and <image>, where k is some integer number in range [1, a].
By <image> we denote the quotient of integer division of x and y. By <image> we denote the remainder of integer division of x and y. You can read more about these operations here: http://goo.gl/AcsXhT.
The answer may be large, so please print its remainder modulo 1 000 000 007 (109 + 7). Can you compute it faster than Dreamoon?
Input
The single line of the input contains two integers a, b (1 ≤ a, b ≤ 107).
Output
Print a single integer representing the answer modulo 1 000 000 007 (109 + 7).
Examples
Input
1 1
Output
0
Input
2 2
Output
8
Note
For the first sample, there are no nice integers because <image> is always zero.
For the second sample, the set of nice integers is {3, 5}.
Tags: math
Correct Solution:
```
a,b = list(map(int,input().split()))
if b ==1 :
print(0)
else :
res = a + b*a*(a+1)//2
res = (res*(b)*(b-1)//2)
print(res%(10**9 +7))
```
| 94,773 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Dreamoon loves summing up something for no reason. One day he obtains two integers a and b occasionally. He wants to calculate the sum of all nice integers. Positive integer x is called nice if <image> and <image>, where k is some integer number in range [1, a].
By <image> we denote the quotient of integer division of x and y. By <image> we denote the remainder of integer division of x and y. You can read more about these operations here: http://goo.gl/AcsXhT.
The answer may be large, so please print its remainder modulo 1 000 000 007 (109 + 7). Can you compute it faster than Dreamoon?
Input
The single line of the input contains two integers a, b (1 ≤ a, b ≤ 107).
Output
Print a single integer representing the answer modulo 1 000 000 007 (109 + 7).
Examples
Input
1 1
Output
0
Input
2 2
Output
8
Note
For the first sample, there are no nice integers because <image> is always zero.
For the second sample, the set of nice integers is {3, 5}.
Tags: math
Correct Solution:
```
a = input()
a = a.split()
a,b = int(a[0]),int(a[1])
k2 = b*(b-1)*a // 2
k = (b-1)*b//2 * b* (1+a)*a // 2
res = (k + k2) % 1000000007
print(res)
```
| 94,774 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Dreamoon loves summing up something for no reason. One day he obtains two integers a and b occasionally. He wants to calculate the sum of all nice integers. Positive integer x is called nice if <image> and <image>, where k is some integer number in range [1, a].
By <image> we denote the quotient of integer division of x and y. By <image> we denote the remainder of integer division of x and y. You can read more about these operations here: http://goo.gl/AcsXhT.
The answer may be large, so please print its remainder modulo 1 000 000 007 (109 + 7). Can you compute it faster than Dreamoon?
Input
The single line of the input contains two integers a, b (1 ≤ a, b ≤ 107).
Output
Print a single integer representing the answer modulo 1 000 000 007 (109 + 7).
Examples
Input
1 1
Output
0
Input
2 2
Output
8
Note
For the first sample, there are no nice integers because <image> is always zero.
For the second sample, the set of nice integers is {3, 5}.
Tags: math
Correct Solution:
```
import sys
import math
MAXNUM = math.inf
MINNUM = -1 * math.inf
ASCIILOWER = 97
ASCIIUPPER = 65
MODMAX = 1000000007
def getInt():
return int(sys.stdin.readline().rstrip())
def getInts():
return map(int, sys.stdin.readline().rstrip().split(" "))
def getString():
return sys.stdin.readline().rstrip()
def printOutput(ans):
sys.stdout.write()
pass
def termadd(n):
return (n * (n + 1)) // 2
def solve(a, b):
return ((a*(b-1)*(b)*(b*(a+1) + 2))//4) % MODMAX
def readinput():
a, b = getInts()
print(solve(a, b))
readinput()
```
| 94,775 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Dreamoon loves summing up something for no reason. One day he obtains two integers a and b occasionally. He wants to calculate the sum of all nice integers. Positive integer x is called nice if <image> and <image>, where k is some integer number in range [1, a].
By <image> we denote the quotient of integer division of x and y. By <image> we denote the remainder of integer division of x and y. You can read more about these operations here: http://goo.gl/AcsXhT.
The answer may be large, so please print its remainder modulo 1 000 000 007 (109 + 7). Can you compute it faster than Dreamoon?
Input
The single line of the input contains two integers a, b (1 ≤ a, b ≤ 107).
Output
Print a single integer representing the answer modulo 1 000 000 007 (109 + 7).
Examples
Input
1 1
Output
0
Input
2 2
Output
8
Note
For the first sample, there are no nice integers because <image> is always zero.
For the second sample, the set of nice integers is {3, 5}.
Submitted Solution:
```
###### ### ####### ####### ## # ##### ### #####
# # # # # # # # # # # # # ###
# # # # # # # # # # # # # ###
###### ######### # # # # # # ######### #
###### ######### # # # # # # ######### #
# # # # # # # # # # #### # # #
# # # # # # # ## # # # # #
###### # # ####### ####### # # ##### # # # #
from __future__ import print_function # for PyPy2
# from itertools import permutations
# from functools import cmp_to_key # for adding custom comparator
# from fractions import Fraction
# from collections import *
from sys import stdin
# from bisect import *
from heapq import *
from math import log2, ceil, sqrt, gcd, log
g = lambda : stdin.readline().strip()
gl = lambda : g().split()
gil = lambda : [int(var) for var in gl()]
gfl = lambda : [float(var) for var in gl()]
gcl = lambda : list(g())
gbs = lambda : [int(var) for var in g()]
rr = lambda x : reversed(range(x))
mod = int(1e9)+7
inf = float("inf")
# range = xrange
a, b = gil()
if b == 1:
print(0)
exit()
ans = 0
for k in range(1, a+1):
ans += (k*b + 1)%mod
if ans >= mod:
ans %= mod
# print(ans)
mul = ((b-1)*(b))//2
mul %= mod
ans *= mul
ans %= mod
print(ans)
```
Yes
| 94,776 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Dreamoon loves summing up something for no reason. One day he obtains two integers a and b occasionally. He wants to calculate the sum of all nice integers. Positive integer x is called nice if <image> and <image>, where k is some integer number in range [1, a].
By <image> we denote the quotient of integer division of x and y. By <image> we denote the remainder of integer division of x and y. You can read more about these operations here: http://goo.gl/AcsXhT.
The answer may be large, so please print its remainder modulo 1 000 000 007 (109 + 7). Can you compute it faster than Dreamoon?
Input
The single line of the input contains two integers a, b (1 ≤ a, b ≤ 107).
Output
Print a single integer representing the answer modulo 1 000 000 007 (109 + 7).
Examples
Input
1 1
Output
0
Input
2 2
Output
8
Note
For the first sample, there are no nice integers because <image> is always zero.
For the second sample, the set of nice integers is {3, 5}.
Submitted Solution:
```
a,b=map(int, input().split())
m=1000000007
B = int((b*(b-1)/2) % m );
A1 = int((a*(a+1)/2) % m );
A = int((A1*b+a) % m );
res = int((A*B) % m) ;#Is the operation divided in fractions of it
print(res)
```
Yes
| 94,777 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Dreamoon loves summing up something for no reason. One day he obtains two integers a and b occasionally. He wants to calculate the sum of all nice integers. Positive integer x is called nice if <image> and <image>, where k is some integer number in range [1, a].
By <image> we denote the quotient of integer division of x and y. By <image> we denote the remainder of integer division of x and y. You can read more about these operations here: http://goo.gl/AcsXhT.
The answer may be large, so please print its remainder modulo 1 000 000 007 (109 + 7). Can you compute it faster than Dreamoon?
Input
The single line of the input contains two integers a, b (1 ≤ a, b ≤ 107).
Output
Print a single integer representing the answer modulo 1 000 000 007 (109 + 7).
Examples
Input
1 1
Output
0
Input
2 2
Output
8
Note
For the first sample, there are no nice integers because <image> is always zero.
For the second sample, the set of nice integers is {3, 5}.
Submitted Solution:
```
x=[int(i) for i in input().split()]
a=x[0]
b=x[1]
x = ((b*(b-1))//2)%(1000000007)
y = (a + (b*a*(a+1))//2)%(1000000007)
print((x*y)%(1000000007))
```
Yes
| 94,778 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Dreamoon loves summing up something for no reason. One day he obtains two integers a and b occasionally. He wants to calculate the sum of all nice integers. Positive integer x is called nice if <image> and <image>, where k is some integer number in range [1, a].
By <image> we denote the quotient of integer division of x and y. By <image> we denote the remainder of integer division of x and y. You can read more about these operations here: http://goo.gl/AcsXhT.
The answer may be large, so please print its remainder modulo 1 000 000 007 (109 + 7). Can you compute it faster than Dreamoon?
Input
The single line of the input contains two integers a, b (1 ≤ a, b ≤ 107).
Output
Print a single integer representing the answer modulo 1 000 000 007 (109 + 7).
Examples
Input
1 1
Output
0
Input
2 2
Output
8
Note
For the first sample, there are no nice integers because <image> is always zero.
For the second sample, the set of nice integers is {3, 5}.
Submitted Solution:
```
'''
Created on Oct 12, 2014
@author: Ismael
'''
#import time
MOD = 10**9+7
def sumTermsArith1(firstTerm,r,nbTerms):
return (nbTerms*(2*firstTerm+(nbTerms-1)*r))//2
def solve(a,b):
s = 0
for rem in range(1,b):
reason = rem*b
s = (s+sumTermsArith1(reason+rem,reason,a))%MOD
return s
def solve2(a,b):
reason = a*(b*(a+1)+2)//2
return sumTermsArith1(reason,reason,b-1)%MOD
#t = time.clock()
a,b = map(int,input().split())
#sol1 = solve(a,b)
sol2 = solve2(a,b)
print(sol2)
#print(sol1 == sol2)
#print(time.clock()-t)
```
Yes
| 94,779 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Dreamoon loves summing up something for no reason. One day he obtains two integers a and b occasionally. He wants to calculate the sum of all nice integers. Positive integer x is called nice if <image> and <image>, where k is some integer number in range [1, a].
By <image> we denote the quotient of integer division of x and y. By <image> we denote the remainder of integer division of x and y. You can read more about these operations here: http://goo.gl/AcsXhT.
The answer may be large, so please print its remainder modulo 1 000 000 007 (109 + 7). Can you compute it faster than Dreamoon?
Input
The single line of the input contains two integers a, b (1 ≤ a, b ≤ 107).
Output
Print a single integer representing the answer modulo 1 000 000 007 (109 + 7).
Examples
Input
1 1
Output
0
Input
2 2
Output
8
Note
For the first sample, there are no nice integers because <image> is always zero.
For the second sample, the set of nice integers is {3, 5}.
Submitted Solution:
```
from sys import stdin
from sys import stdout
def get():
return stdin.readline().strip()
def getf():
return [int(i) for i in get().split()]
def put(a, end = "\n"):
stdout.write(str(a) + end)
def putf(a):
stdout.write(" ".join([str(i) for i in a]) + "\n")
def main():
a, b = getf()
m = 1000000007
ans = (b * (b - 1) // 2) * a * (1 + b * (a + 1) // 2) % m
put(ans)
main()
```
No
| 94,780 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Dreamoon loves summing up something for no reason. One day he obtains two integers a and b occasionally. He wants to calculate the sum of all nice integers. Positive integer x is called nice if <image> and <image>, where k is some integer number in range [1, a].
By <image> we denote the quotient of integer division of x and y. By <image> we denote the remainder of integer division of x and y. You can read more about these operations here: http://goo.gl/AcsXhT.
The answer may be large, so please print its remainder modulo 1 000 000 007 (109 + 7). Can you compute it faster than Dreamoon?
Input
The single line of the input contains two integers a, b (1 ≤ a, b ≤ 107).
Output
Print a single integer representing the answer modulo 1 000 000 007 (109 + 7).
Examples
Input
1 1
Output
0
Input
2 2
Output
8
Note
For the first sample, there are no nice integers because <image> is always zero.
For the second sample, the set of nice integers is {3, 5}.
Submitted Solution:
```
import sys
import math
MAXNUM = math.inf
MINNUM = -1 * math.inf
ASCIILOWER = 97
ASCIIUPPER = 65
MODMAX = 1000000007
def getInt():
return int(sys.stdin.readline().rstrip())
def getInts():
return map(int, sys.stdin.readline().rstrip().split(" "))
def getString():
return sys.stdin.readline().rstrip()
def printOutput(ans):
sys.stdout.write()
pass
def termadd(n):
return (n * (n + 1)) // 2
def solve(a, b):
multtotal = 0
addtotal = 0
divadd = 1
while divadd < b and a // divadd != 0:
multtotal += (termadd(a // divadd) * divadd) % MODMAX
addtotal += ((a // divadd) * divadd) % MODMAX
divadd += 1
multtotal *= b
return (addtotal + multtotal) % MODMAX
def readinput():
a, b = getInts()
print(solve(a, b))
readinput()
```
No
| 94,781 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Dreamoon loves summing up something for no reason. One day he obtains two integers a and b occasionally. He wants to calculate the sum of all nice integers. Positive integer x is called nice if <image> and <image>, where k is some integer number in range [1, a].
By <image> we denote the quotient of integer division of x and y. By <image> we denote the remainder of integer division of x and y. You can read more about these operations here: http://goo.gl/AcsXhT.
The answer may be large, so please print its remainder modulo 1 000 000 007 (109 + 7). Can you compute it faster than Dreamoon?
Input
The single line of the input contains two integers a, b (1 ≤ a, b ≤ 107).
Output
Print a single integer representing the answer modulo 1 000 000 007 (109 + 7).
Examples
Input
1 1
Output
0
Input
2 2
Output
8
Note
For the first sample, there are no nice integers because <image> is always zero.
For the second sample, the set of nice integers is {3, 5}.
Submitted Solution:
```
a,b=map(int, input().split())
k=1
res=0
while k<=a:
res+=((k*b)+1)*((b*(b-1))/2)
k+=1
print(int(res))
```
No
| 94,782 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Dreamoon loves summing up something for no reason. One day he obtains two integers a and b occasionally. He wants to calculate the sum of all nice integers. Positive integer x is called nice if <image> and <image>, where k is some integer number in range [1, a].
By <image> we denote the quotient of integer division of x and y. By <image> we denote the remainder of integer division of x and y. You can read more about these operations here: http://goo.gl/AcsXhT.
The answer may be large, so please print its remainder modulo 1 000 000 007 (109 + 7). Can you compute it faster than Dreamoon?
Input
The single line of the input contains two integers a, b (1 ≤ a, b ≤ 107).
Output
Print a single integer representing the answer modulo 1 000 000 007 (109 + 7).
Examples
Input
1 1
Output
0
Input
2 2
Output
8
Note
For the first sample, there are no nice integers because <image> is always zero.
For the second sample, the set of nice integers is {3, 5}.
Submitted Solution:
```
mod =10**9+7
b,x = map(int,input().split())
t = (b*(b-1)/2)%mod
ans = (t * ((x *(x+1)/2 * b) %mod+ x))%mod
print(int(ans))
```
No
| 94,783 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Vasya and Petya have invented a new game. Vasya takes a stripe consisting of 1 × n square and paints the squares black and white. After that Petya can start moves — during a move he may choose any two neighboring squares of one color and repaint these two squares any way he wants, perhaps in different colors. Petya can only repaint the squares in white and black colors. Petya’s aim is to repaint the stripe so that no two neighboring squares were of one color. Help Petya, using the given initial coloring, find the minimum number of moves Petya needs to win.
Input
The first line contains number n (1 ≤ n ≤ 1000) which represents the stripe’s length. The second line contains exactly n symbols — the line’s initial coloring. 0 corresponds to a white square, 1 corresponds to a black one.
Output
If Petya cannot win with such an initial coloring, print -1. Otherwise print the minimum number of moves Petya needs to win.
Examples
Input
6
111010
Output
1
Input
5
10001
Output
1
Input
7
1100010
Output
2
Input
5
00100
Output
2
Note
In the first sample Petya can take squares 1 and 2. He repaints square 1 to black and square 2 to white.
In the second sample Petya can take squares 2 and 3. He repaints square 2 to white and square 3 to black.
Tags: brute force, dp, implementation
Correct Solution:
```
n = int(input())
stripe = list(input())
for i in range(n):
stripe[i] = int(stripe[i])
w = 0
b = 0
for i in range(n):
if i % 2 == stripe[i] - 0:
w += 1
else:
b += 1
answer = min (w, b)
print(answer)
```
| 94,784 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Vasya and Petya have invented a new game. Vasya takes a stripe consisting of 1 × n square and paints the squares black and white. After that Petya can start moves — during a move he may choose any two neighboring squares of one color and repaint these two squares any way he wants, perhaps in different colors. Petya can only repaint the squares in white and black colors. Petya’s aim is to repaint the stripe so that no two neighboring squares were of one color. Help Petya, using the given initial coloring, find the minimum number of moves Petya needs to win.
Input
The first line contains number n (1 ≤ n ≤ 1000) which represents the stripe’s length. The second line contains exactly n symbols — the line’s initial coloring. 0 corresponds to a white square, 1 corresponds to a black one.
Output
If Petya cannot win with such an initial coloring, print -1. Otherwise print the minimum number of moves Petya needs to win.
Examples
Input
6
111010
Output
1
Input
5
10001
Output
1
Input
7
1100010
Output
2
Input
5
00100
Output
2
Note
In the first sample Petya can take squares 1 and 2. He repaints square 1 to black and square 2 to white.
In the second sample Petya can take squares 2 and 3. He repaints square 2 to white and square 3 to black.
Tags: brute force, dp, implementation
Correct Solution:
```
n=int(input())
s=input()
t=0
for i in range(n):
if (i+1)%2==0 and s[i]=="1" or (i+1)%2==1 and s[i]=="0":
t+=1
print(min(t,n-t))
```
| 94,785 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Vasya and Petya have invented a new game. Vasya takes a stripe consisting of 1 × n square and paints the squares black and white. After that Petya can start moves — during a move he may choose any two neighboring squares of one color and repaint these two squares any way he wants, perhaps in different colors. Petya can only repaint the squares in white and black colors. Petya’s aim is to repaint the stripe so that no two neighboring squares were of one color. Help Petya, using the given initial coloring, find the minimum number of moves Petya needs to win.
Input
The first line contains number n (1 ≤ n ≤ 1000) which represents the stripe’s length. The second line contains exactly n symbols — the line’s initial coloring. 0 corresponds to a white square, 1 corresponds to a black one.
Output
If Petya cannot win with such an initial coloring, print -1. Otherwise print the minimum number of moves Petya needs to win.
Examples
Input
6
111010
Output
1
Input
5
10001
Output
1
Input
7
1100010
Output
2
Input
5
00100
Output
2
Note
In the first sample Petya can take squares 1 and 2. He repaints square 1 to black and square 2 to white.
In the second sample Petya can take squares 2 and 3. He repaints square 2 to white and square 3 to black.
Tags: brute force, dp, implementation
Correct Solution:
```
import sys
from array import array # noqa: F401
from itertools import product
def input():
return sys.stdin.buffer.readline().decode('utf-8')
n = int(input())
s = list(map(int, input().rstrip()))
if n <= 2:
if n == 1 or s[0] != s[1]:
print(0)
else:
print(1)
exit()
inf = 10**9
dp = [inf] * 4
dp[2 * s[0] + s[1]] = 0
for index, d in enumerate(s[2:], start=2):
next_dp = [inf] * 4
for i, j in product((0, 2), (0, 1)):
if i == j * 2:
next_dp[(j ^ 1) * 2 + d] = min(next_dp[(j ^ 1) * 2 + d], dp[i + j] + 1, dp[i + j] + index - 1)
next_dp[j * 2 + d] = min(next_dp[j * 2 + d], dp[i + j] + index - 1)
else:
next_dp[j * 2 + d] = min(next_dp[j * 2 + d], dp[i + j])
if j == d:
next_dp[(j ^ 1) * 2 + d] = min(next_dp[(j ^ 1) * 2 + d], dp[i + j] + index)
dp = next_dp
ans = min(
dp[0] + 1,
dp[1],
dp[2],
dp[3] + 1
)
print(ans if ans < inf else -1)
```
| 94,786 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Vasya and Petya have invented a new game. Vasya takes a stripe consisting of 1 × n square and paints the squares black and white. After that Petya can start moves — during a move he may choose any two neighboring squares of one color and repaint these two squares any way he wants, perhaps in different colors. Petya can only repaint the squares in white and black colors. Petya’s aim is to repaint the stripe so that no two neighboring squares were of one color. Help Petya, using the given initial coloring, find the minimum number of moves Petya needs to win.
Input
The first line contains number n (1 ≤ n ≤ 1000) which represents the stripe’s length. The second line contains exactly n symbols — the line’s initial coloring. 0 corresponds to a white square, 1 corresponds to a black one.
Output
If Petya cannot win with such an initial coloring, print -1. Otherwise print the minimum number of moves Petya needs to win.
Examples
Input
6
111010
Output
1
Input
5
10001
Output
1
Input
7
1100010
Output
2
Input
5
00100
Output
2
Note
In the first sample Petya can take squares 1 and 2. He repaints square 1 to black and square 2 to white.
In the second sample Petya can take squares 2 and 3. He repaints square 2 to white and square 3 to black.
Tags: brute force, dp, implementation
Correct Solution:
```
n = int(input())
s = input()
l = []
for i in range(n):
l.append(int(s[i]))
ans = 0
for i in range(1, n):
if l[i] == l[i-1]:
l[i] ^= 1
ans = ans+1
print(min(ans, n-ans))
# Made By Mostafa_Khaled
```
| 94,787 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Vasya and Petya have invented a new game. Vasya takes a stripe consisting of 1 × n square and paints the squares black and white. After that Petya can start moves — during a move he may choose any two neighboring squares of one color and repaint these two squares any way he wants, perhaps in different colors. Petya can only repaint the squares in white and black colors. Petya’s aim is to repaint the stripe so that no two neighboring squares were of one color. Help Petya, using the given initial coloring, find the minimum number of moves Petya needs to win.
Input
The first line contains number n (1 ≤ n ≤ 1000) which represents the stripe’s length. The second line contains exactly n symbols — the line’s initial coloring. 0 corresponds to a white square, 1 corresponds to a black one.
Output
If Petya cannot win with such an initial coloring, print -1. Otherwise print the minimum number of moves Petya needs to win.
Examples
Input
6
111010
Output
1
Input
5
10001
Output
1
Input
7
1100010
Output
2
Input
5
00100
Output
2
Note
In the first sample Petya can take squares 1 and 2. He repaints square 1 to black and square 2 to white.
In the second sample Petya can take squares 2 and 3. He repaints square 2 to white and square 3 to black.
Tags: brute force, dp, implementation
Correct Solution:
```
input()
a = list(input())
l = len(a)
if l % 2 == 0:
s = list("10" * (l // 2))
d = list("01" * (l // 2))
else:
s = list("10" * (l // 2) + "1")
d = list("01" * (l // 2) + "0")
d_s = 0
d_d = 0
for i in range(len(a)):
if a[i] != s[i]:
d_s += 1
if a[i] != d[i]:
d_d += 1
print(min(d_s,d_d))
```
| 94,788 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Vasya and Petya have invented a new game. Vasya takes a stripe consisting of 1 × n square and paints the squares black and white. After that Petya can start moves — during a move he may choose any two neighboring squares of one color and repaint these two squares any way he wants, perhaps in different colors. Petya can only repaint the squares in white and black colors. Petya’s aim is to repaint the stripe so that no two neighboring squares were of one color. Help Petya, using the given initial coloring, find the minimum number of moves Petya needs to win.
Input
The first line contains number n (1 ≤ n ≤ 1000) which represents the stripe’s length. The second line contains exactly n symbols — the line’s initial coloring. 0 corresponds to a white square, 1 corresponds to a black one.
Output
If Petya cannot win with such an initial coloring, print -1. Otherwise print the minimum number of moves Petya needs to win.
Examples
Input
6
111010
Output
1
Input
5
10001
Output
1
Input
7
1100010
Output
2
Input
5
00100
Output
2
Note
In the first sample Petya can take squares 1 and 2. He repaints square 1 to black and square 2 to white.
In the second sample Petya can take squares 2 and 3. He repaints square 2 to white and square 3 to black.
Tags: brute force, dp, implementation
Correct Solution:
```
n = int(input())
s = input()
l = []
for i in range(n):
l.append(int(s[i]))
ans = 0
for i in range(1, n):
if l[i] == l[i-1]:
l[i] ^= 1
ans = ans+1
print(min(ans, n-ans))
```
| 94,789 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Vasya and Petya have invented a new game. Vasya takes a stripe consisting of 1 × n square and paints the squares black and white. After that Petya can start moves — during a move he may choose any two neighboring squares of one color and repaint these two squares any way he wants, perhaps in different colors. Petya can only repaint the squares in white and black colors. Petya’s aim is to repaint the stripe so that no two neighboring squares were of one color. Help Petya, using the given initial coloring, find the minimum number of moves Petya needs to win.
Input
The first line contains number n (1 ≤ n ≤ 1000) which represents the stripe’s length. The second line contains exactly n symbols — the line’s initial coloring. 0 corresponds to a white square, 1 corresponds to a black one.
Output
If Petya cannot win with such an initial coloring, print -1. Otherwise print the minimum number of moves Petya needs to win.
Examples
Input
6
111010
Output
1
Input
5
10001
Output
1
Input
7
1100010
Output
2
Input
5
00100
Output
2
Note
In the first sample Petya can take squares 1 and 2. He repaints square 1 to black and square 2 to white.
In the second sample Petya can take squares 2 and 3. He repaints square 2 to white and square 3 to black.
Tags: brute force, dp, implementation
Correct Solution:
```
n = int(input())
seq = input()
seq = [int(x) for x in seq]
count = [[0,0],[0,0]]
for i in range(n):
count[i%2][seq[i]] += 1
m1 = count[0][1] + count[1][0]
m2 = count[0][0] + count[1][1]
print(min(m1,m2))
```
| 94,790 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Vasya and Petya have invented a new game. Vasya takes a stripe consisting of 1 × n square and paints the squares black and white. After that Petya can start moves — during a move he may choose any two neighboring squares of one color and repaint these two squares any way he wants, perhaps in different colors. Petya can only repaint the squares in white and black colors. Petya’s aim is to repaint the stripe so that no two neighboring squares were of one color. Help Petya, using the given initial coloring, find the minimum number of moves Petya needs to win.
Input
The first line contains number n (1 ≤ n ≤ 1000) which represents the stripe’s length. The second line contains exactly n symbols — the line’s initial coloring. 0 corresponds to a white square, 1 corresponds to a black one.
Output
If Petya cannot win with such an initial coloring, print -1. Otherwise print the minimum number of moves Petya needs to win.
Examples
Input
6
111010
Output
1
Input
5
10001
Output
1
Input
7
1100010
Output
2
Input
5
00100
Output
2
Note
In the first sample Petya can take squares 1 and 2. He repaints square 1 to black and square 2 to white.
In the second sample Petya can take squares 2 and 3. He repaints square 2 to white and square 3 to black.
Tags: brute force, dp, implementation
Correct Solution:
```
n=int(input())
def hamming(a,b):
global n
ret=0
for i in range(n):
ret+=int(a[i]!=b[i])
return ret
s=input()
a=['0' if q%2==0 else '1' for q in range(n)]
b=['0' if q%2==1 else '1' for q in range(n)]
print(min(hamming(s,a),hamming(s,b)))
```
| 94,791 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Vasya and Petya have invented a new game. Vasya takes a stripe consisting of 1 × n square and paints the squares black and white. After that Petya can start moves — during a move he may choose any two neighboring squares of one color and repaint these two squares any way he wants, perhaps in different colors. Petya can only repaint the squares in white and black colors. Petya’s aim is to repaint the stripe so that no two neighboring squares were of one color. Help Petya, using the given initial coloring, find the minimum number of moves Petya needs to win.
Input
The first line contains number n (1 ≤ n ≤ 1000) which represents the stripe’s length. The second line contains exactly n symbols — the line’s initial coloring. 0 corresponds to a white square, 1 corresponds to a black one.
Output
If Petya cannot win with such an initial coloring, print -1. Otherwise print the minimum number of moves Petya needs to win.
Examples
Input
6
111010
Output
1
Input
5
10001
Output
1
Input
7
1100010
Output
2
Input
5
00100
Output
2
Note
In the first sample Petya can take squares 1 and 2. He repaints square 1 to black and square 2 to white.
In the second sample Petya can take squares 2 and 3. He repaints square 2 to white and square 3 to black.
Submitted Solution:
```
n=int(input())
x=str(input())
dp1,dp2=0,0
for i in range(n):
if i%2==0:
if x[i]=="0":
dp1+=1
else:
dp2+=1
if i%2==1:
if x[i]=="0":
dp2+=1
else:
dp1+=1
print(min(dp1,dp2))
```
Yes
| 94,792 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Vasya and Petya have invented a new game. Vasya takes a stripe consisting of 1 × n square and paints the squares black and white. After that Petya can start moves — during a move he may choose any two neighboring squares of one color and repaint these two squares any way he wants, perhaps in different colors. Petya can only repaint the squares in white and black colors. Petya’s aim is to repaint the stripe so that no two neighboring squares were of one color. Help Petya, using the given initial coloring, find the minimum number of moves Petya needs to win.
Input
The first line contains number n (1 ≤ n ≤ 1000) which represents the stripe’s length. The second line contains exactly n symbols — the line’s initial coloring. 0 corresponds to a white square, 1 corresponds to a black one.
Output
If Petya cannot win with such an initial coloring, print -1. Otherwise print the minimum number of moves Petya needs to win.
Examples
Input
6
111010
Output
1
Input
5
10001
Output
1
Input
7
1100010
Output
2
Input
5
00100
Output
2
Note
In the first sample Petya can take squares 1 and 2. He repaints square 1 to black and square 2 to white.
In the second sample Petya can take squares 2 and 3. He repaints square 2 to white and square 3 to black.
Submitted Solution:
```
n = int(input());s2 = "";s1 = "";bit=input();s1+='0'
for i in range(1,n):
if(s1[i-1] == '0'):
s1+='1'
else:
s1+='0'
s2+='1'
for i in range(1,n):
if(s2[i-1] == '0'):
s2+='1'
else:
s2+='0'
#print(s1,s2)
cnt1 = 0;cnt2 = 0
for i in range(0,n):
if(bit[i]!=s1[i]):
cnt1+=1;
for i in range(0,n):
if(bit[i]!=s2[i]):
cnt2+=1;
print(min(cnt1,cnt2))
```
Yes
| 94,793 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Vasya and Petya have invented a new game. Vasya takes a stripe consisting of 1 × n square and paints the squares black and white. After that Petya can start moves — during a move he may choose any two neighboring squares of one color and repaint these two squares any way he wants, perhaps in different colors. Petya can only repaint the squares in white and black colors. Petya’s aim is to repaint the stripe so that no two neighboring squares were of one color. Help Petya, using the given initial coloring, find the minimum number of moves Petya needs to win.
Input
The first line contains number n (1 ≤ n ≤ 1000) which represents the stripe’s length. The second line contains exactly n symbols — the line’s initial coloring. 0 corresponds to a white square, 1 corresponds to a black one.
Output
If Petya cannot win with such an initial coloring, print -1. Otherwise print the minimum number of moves Petya needs to win.
Examples
Input
6
111010
Output
1
Input
5
10001
Output
1
Input
7
1100010
Output
2
Input
5
00100
Output
2
Note
In the first sample Petya can take squares 1 and 2. He repaints square 1 to black and square 2 to white.
In the second sample Petya can take squares 2 and 3. He repaints square 2 to white and square 3 to black.
Submitted Solution:
```
def do(s, n):
for i in range(1, n):
if s[i-1] == '0':
s += '1'
else :
s += '0'
return s
n = int(input())
ss = input()
str1 = "1";
s1 = do(str1, n)
str1 = "0"
s2 = do(str1, n)
cnt = 0
cnt1 = 0
for i in range(0, n):
if ss[i] != s1[i]:
cnt += 1
for i in range(0, n):
if ss[i] != s2[i]:
cnt1 += 1
print(min(cnt, cnt1))
```
Yes
| 94,794 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Vasya and Petya have invented a new game. Vasya takes a stripe consisting of 1 × n square and paints the squares black and white. After that Petya can start moves — during a move he may choose any two neighboring squares of one color and repaint these two squares any way he wants, perhaps in different colors. Petya can only repaint the squares in white and black colors. Petya’s aim is to repaint the stripe so that no two neighboring squares were of one color. Help Petya, using the given initial coloring, find the minimum number of moves Petya needs to win.
Input
The first line contains number n (1 ≤ n ≤ 1000) which represents the stripe’s length. The second line contains exactly n symbols — the line’s initial coloring. 0 corresponds to a white square, 1 corresponds to a black one.
Output
If Petya cannot win with such an initial coloring, print -1. Otherwise print the minimum number of moves Petya needs to win.
Examples
Input
6
111010
Output
1
Input
5
10001
Output
1
Input
7
1100010
Output
2
Input
5
00100
Output
2
Note
In the first sample Petya can take squares 1 and 2. He repaints square 1 to black and square 2 to white.
In the second sample Petya can take squares 2 and 3. He repaints square 2 to white and square 3 to black.
Submitted Solution:
```
#Code by Sounak, IIESTS
#------------------------------warmup----------------------------
import os
import sys
import math
from io import BytesIO, IOBase
from fractions import Fraction
from collections import defaultdict
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())
s=list(input())
s=[int(s[i]) for i in range(n)]
ans=0
for i in range(n):
if i%2==0:
ans+=s[i]
else:
ans+=1-s[i]
m=ans
ans=0
for i in range(n):
if i%2==0:
ans+=1-s[i]
else:
ans+=s[i]
print(min(m,ans))
```
Yes
| 94,795 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Vasya and Petya have invented a new game. Vasya takes a stripe consisting of 1 × n square and paints the squares black and white. After that Petya can start moves — during a move he may choose any two neighboring squares of one color and repaint these two squares any way he wants, perhaps in different colors. Petya can only repaint the squares in white and black colors. Petya’s aim is to repaint the stripe so that no two neighboring squares were of one color. Help Petya, using the given initial coloring, find the minimum number of moves Petya needs to win.
Input
The first line contains number n (1 ≤ n ≤ 1000) which represents the stripe’s length. The second line contains exactly n symbols — the line’s initial coloring. 0 corresponds to a white square, 1 corresponds to a black one.
Output
If Petya cannot win with such an initial coloring, print -1. Otherwise print the minimum number of moves Petya needs to win.
Examples
Input
6
111010
Output
1
Input
5
10001
Output
1
Input
7
1100010
Output
2
Input
5
00100
Output
2
Note
In the first sample Petya can take squares 1 and 2. He repaints square 1 to black and square 2 to white.
In the second sample Petya can take squares 2 and 3. He repaints square 2 to white and square 3 to black.
Submitted Solution:
```
import sys
from array import array # noqa: F401
from itertools import product
def input():
return sys.stdin.buffer.readline().decode('utf-8')
n = int(input())
s = list(map(int, input().rstrip()))
if n <= 2:
if n == 1 or s[0] != s[1]:
print(0)
else:
print(1)
exit()
inf = 10**9
dp = [inf] * 4
dp[2 * s[0] + s[1]] = 0
if s[0] == s[1]:
dp[1] = dp[2] = 1
for d in s[2:]:
next_dp = [inf] * 4
for i, j in product((0, 2), (0, 1)):
if i == j * 2 or j == d:
next_dp[(j ^ 1) * 2 + d] = min(next_dp[(j ^ 1) * 2 + d], dp[i + j] + 1)
if j == d:
next_dp[j * 2 + (d ^ 1)] = min(next_dp[j * 2 + (d ^ 1)], dp[i + j] + 1)
if i != j * 2:
next_dp[j * 2 + d] = min(next_dp[j * 2 + d], dp[i + j])
dp = next_dp
ans = min(
dp[0] + 1,
dp[1],
dp[2],
dp[3] + 1
)
print(ans if ans < inf else -1)
```
No
| 94,796 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Vasya and Petya have invented a new game. Vasya takes a stripe consisting of 1 × n square and paints the squares black and white. After that Petya can start moves — during a move he may choose any two neighboring squares of one color and repaint these two squares any way he wants, perhaps in different colors. Petya can only repaint the squares in white and black colors. Petya’s aim is to repaint the stripe so that no two neighboring squares were of one color. Help Petya, using the given initial coloring, find the minimum number of moves Petya needs to win.
Input
The first line contains number n (1 ≤ n ≤ 1000) which represents the stripe’s length. The second line contains exactly n symbols — the line’s initial coloring. 0 corresponds to a white square, 1 corresponds to a black one.
Output
If Petya cannot win with such an initial coloring, print -1. Otherwise print the minimum number of moves Petya needs to win.
Examples
Input
6
111010
Output
1
Input
5
10001
Output
1
Input
7
1100010
Output
2
Input
5
00100
Output
2
Note
In the first sample Petya can take squares 1 and 2. He repaints square 1 to black and square 2 to white.
In the second sample Petya can take squares 2 and 3. He repaints square 2 to white and square 3 to black.
Submitted Solution:
```
# ---------------------------iye ha aam zindegi---------------------------------------------
import math
import heapq, bisect
import sys
from collections import deque, defaultdict
from fractions import Fraction
mod = 10 ** 9 + 7
mod1 = 998244353
# ------------------------------warmup----------------------------
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")
# -------------------game starts now----------------------------------------------------import math
class TreeNode:
def __init__(self, k, v):
self.key = k
self.value = v
self.left = None
self.right = None
self.parent = None
self.height = 1
self.num_left = 1
self.num_total = 1
class AvlTree:
def __init__(self):
self._tree = None
def add(self, k, v):
if not self._tree:
self._tree = TreeNode(k, v)
return
node = self._add(k, v)
if node:
self._rebalance(node)
def _add(self, k, v):
node = self._tree
while node:
if k < node.key:
if node.left:
node = node.left
else:
node.left = TreeNode(k, v)
node.left.parent = node
return node.left
elif node.key < k:
if node.right:
node = node.right
else:
node.right = TreeNode(k, v)
node.right.parent = node
return node.right
else:
node.value = v
return
@staticmethod
def get_height(x):
return x.height if x else 0
@staticmethod
def get_num_total(x):
return x.num_total if x else 0
def _rebalance(self, node):
n = node
while n:
lh = self.get_height(n.left)
rh = self.get_height(n.right)
n.height = max(lh, rh) + 1
balance_factor = lh - rh
n.num_total = 1 + self.get_num_total(n.left) + self.get_num_total(n.right)
n.num_left = 1 + self.get_num_total(n.left)
if balance_factor > 1:
if self.get_height(n.left.left) < self.get_height(n.left.right):
self._rotate_left(n.left)
self._rotate_right(n)
elif balance_factor < -1:
if self.get_height(n.right.right) < self.get_height(n.right.left):
self._rotate_right(n.right)
self._rotate_left(n)
else:
n = n.parent
def _remove_one(self, node):
"""
Side effect!!! Changes node. Node should have exactly one child
"""
replacement = node.left or node.right
if node.parent:
if AvlTree._is_left(node):
node.parent.left = replacement
else:
node.parent.right = replacement
replacement.parent = node.parent
node.parent = None
else:
self._tree = replacement
replacement.parent = None
node.left = None
node.right = None
node.parent = None
self._rebalance(replacement)
def _remove_leaf(self, node):
if node.parent:
if AvlTree._is_left(node):
node.parent.left = None
else:
node.parent.right = None
self._rebalance(node.parent)
else:
self._tree = None
node.parent = None
node.left = None
node.right = None
def remove(self, k):
node = self._get_node(k)
if not node:
return
if AvlTree._is_leaf(node):
self._remove_leaf(node)
return
if node.left and node.right:
nxt = AvlTree._get_next(node)
node.key = nxt.key
node.value = nxt.value
if self._is_leaf(nxt):
self._remove_leaf(nxt)
else:
self._remove_one(nxt)
self._rebalance(node)
else:
self._remove_one(node)
def get(self, k):
node = self._get_node(k)
return node.value if node else -1
def _get_node(self, k):
if not self._tree:
return None
node = self._tree
while node:
if k < node.key:
node = node.left
elif node.key < k:
node = node.right
else:
return node
return None
def get_at(self, pos):
x = pos + 1
node = self._tree
while node:
if x < node.num_left:
node = node.left
elif node.num_left < x:
x -= node.num_left
node = node.right
else:
return (node.key, node.value)
raise IndexError("Out of ranges")
@staticmethod
def _is_left(node):
return node.parent.left and node.parent.left == node
@staticmethod
def _is_leaf(node):
return node.left is None and node.right is None
def _rotate_right(self, node):
if not node.parent:
self._tree = node.left
node.left.parent = None
elif AvlTree._is_left(node):
node.parent.left = node.left
node.left.parent = node.parent
else:
node.parent.right = node.left
node.left.parent = node.parent
bk = node.left.right
node.left.right = node
node.parent = node.left
node.left = bk
if bk:
bk.parent = node
node.height = max(self.get_height(node.left), self.get_height(node.right)) + 1
node.num_total = 1 + self.get_num_total(node.left) + self.get_num_total(node.right)
node.num_left = 1 + self.get_num_total(node.left)
def _rotate_left(self, node):
if not node.parent:
self._tree = node.right
node.right.parent = None
elif AvlTree._is_left(node):
node.parent.left = node.right
node.right.parent = node.parent
else:
node.parent.right = node.right
node.right.parent = node.parent
bk = node.right.left
node.right.left = node
node.parent = node.right
node.right = bk
if bk:
bk.parent = node
node.height = max(self.get_height(node.left), self.get_height(node.right)) + 1
node.num_total = 1 + self.get_num_total(node.left) + self.get_num_total(node.right)
node.num_left = 1 + self.get_num_total(node.left)
@staticmethod
def _get_next(node):
if not node.right:
return node.parent
n = node.right
while n.left:
n = n.left
return n
avl=AvlTree()
#-----------------------------------------------binary seacrh tree---------------------------------------
class SegmentTree1:
def __init__(self, data, default='z', func=lambda a, b: min(a ,b)):
"""initialize the segment tree with data"""
self._default = default
self._func = func
self._len = len(data)
self._size = _size = 1 << (self._len - 1).bit_length()
self.data = [default] * (2 * _size)
self.data[_size:_size + self._len] = data
for i in reversed(range(_size)):
self.data[i] = func(self.data[i + i], self.data[i + i + 1])
def __delitem__(self, idx):
self[idx] = self._default
def __getitem__(self, idx):
return self.data[idx + self._size]
def __setitem__(self, idx, value):
idx += self._size
self.data[idx] = value
idx >>= 1
while idx:
self.data[idx] = self._func(self.data[2 * idx], self.data[2 * idx + 1])
idx >>= 1
def __len__(self):
return self._len
def query(self, start, stop):
if start == stop:
return self.__getitem__(start)
stop += 1
start += self._size
stop += self._size
res = self._default
while start < stop:
if start & 1:
res = self._func(res, self.data[start])
start += 1
if stop & 1:
stop -= 1
res = self._func(res, self.data[stop])
start >>= 1
stop >>= 1
return res
def __repr__(self):
return "SegmentTree({0})".format(self.data)
# -------------------game starts now----------------------------------------------------import math
class SegmentTree:
def __init__(self, data, default=0, func=lambda a, b: a + b):
"""initialize the segment tree with data"""
self._default = default
self._func = func
self._len = len(data)
self._size = _size = 1 << (self._len - 1).bit_length()
self.data = [default] * (2 * _size)
self.data[_size:_size + self._len] = data
for i in reversed(range(_size)):
self.data[i] = func(self.data[i + i], self.data[i + i + 1])
def __delitem__(self, idx):
self[idx] = self._default
def __getitem__(self, idx):
return self.data[idx + self._size]
def __setitem__(self, idx, value):
idx += self._size
self.data[idx] = value
idx >>= 1
while idx:
self.data[idx] = self._func(self.data[2 * idx], self.data[2 * idx + 1])
idx >>= 1
def __len__(self):
return self._len
def query(self, start, stop):
if start == stop:
return self.__getitem__(start)
stop += 1
start += self._size
stop += self._size
res = self._default
while start < stop:
if start & 1:
res = self._func(res, self.data[start])
start += 1
if stop & 1:
stop -= 1
res = self._func(res, self.data[stop])
start >>= 1
stop >>= 1
return res
def __repr__(self):
return "SegmentTree({0})".format(self.data)
# -------------------------------iye ha chutiya zindegi-------------------------------------
class Factorial:
def __init__(self, MOD):
self.MOD = MOD
self.factorials = [1, 1]
self.invModulos = [0, 1]
self.invFactorial_ = [1, 1]
def calc(self, n):
if n <= -1:
print("Invalid argument to calculate n!")
print("n must be non-negative value. But the argument was " + str(n))
exit()
if n < len(self.factorials):
return self.factorials[n]
nextArr = [0] * (n + 1 - len(self.factorials))
initialI = len(self.factorials)
prev = self.factorials[-1]
m = self.MOD
for i in range(initialI, n + 1):
prev = nextArr[i - initialI] = prev * i % m
self.factorials += nextArr
return self.factorials[n]
def inv(self, n):
if n <= -1:
print("Invalid argument to calculate n^(-1)")
print("n must be non-negative value. But the argument was " + str(n))
exit()
p = self.MOD
pi = n % p
if pi < len(self.invModulos):
return self.invModulos[pi]
nextArr = [0] * (n + 1 - len(self.invModulos))
initialI = len(self.invModulos)
for i in range(initialI, min(p, n + 1)):
next = -self.invModulos[p % i] * (p // i) % p
self.invModulos.append(next)
return self.invModulos[pi]
def invFactorial(self, n):
if n <= -1:
print("Invalid argument to calculate (n^(-1))!")
print("n must be non-negative value. But the argument was " + str(n))
exit()
if n < len(self.invFactorial_):
return self.invFactorial_[n]
self.inv(n) # To make sure already calculated n^-1
nextArr = [0] * (n + 1 - len(self.invFactorial_))
initialI = len(self.invFactorial_)
prev = self.invFactorial_[-1]
p = self.MOD
for i in range(initialI, n + 1):
prev = nextArr[i - initialI] = (prev * self.invModulos[i % p]) % p
self.invFactorial_ += nextArr
return self.invFactorial_[n]
class Combination:
def __init__(self, MOD):
self.MOD = MOD
self.factorial = Factorial(MOD)
def ncr(self, n, k):
if k < 0 or n < k:
return 0
k = min(k, n - k)
f = self.factorial
return f.calc(n) * f.invFactorial(max(n - k, k)) * f.invFactorial(min(k, n - k)) % self.MOD
# --------------------------------------iye ha combinations ka zindegi---------------------------------
def powm(a, n, m):
if a == 1 or n == 0:
return 1
if n % 2 == 0:
s = powm(a, n // 2, m)
return s * s % m
else:
return a * powm(a, n - 1, m) % m
# --------------------------------------iye ha power ka zindegi---------------------------------
def sort_list(list1, list2):
zipped_pairs = zip(list2, list1)
z = [x for _, x in sorted(zipped_pairs)]
return z
# --------------------------------------------------product----------------------------------------
def product(l):
por = 1
for i in range(len(l)):
por *= l[i]
return por
# --------------------------------------------------binary----------------------------------------
def binarySearchCount(arr, n, key):
left = 0
right = n - 1
count = 0
while (left <= right):
mid = int((right + left)/ 2)
# Check if middle element is
# less than or equal to key
if (arr[mid]<=key):
count = mid+1
left = mid + 1
# If key is smaller, ignore right half
else:
right = mid - 1
return count
# --------------------------------------------------binary----------------------------------------
def countdig(n):
c = 0
while (n > 0):
n //= 10
c += 1
return c
def countGreater( arr,n, k):
l = 0
r = n - 1
# Stores the index of the left most element
# from the array which is greater than k
leftGreater = n
# Finds number of elements greater than k
while (l <= r):
m = int(l + (r - l) / 2)
if (arr[m] >= k):
leftGreater = m
r = m - 1
# If mid element is less than
# or equal to k update l
else:
l = m + 1
# Return the count of elements
# greater than k
return (n - leftGreater)
# --------------------------------------------------binary------------------------------------
n=int(input())
s=list(input())
s=[int(s[i]) for i in range(n)]
ans=0
a=[]
c=1
for i in range(1,n):
if s[i-1]==s[i]:
c+=1
else:
a.append(c)
c=1
if c>0:
a.append(c)
for i in range(len(a)):
if a[i]==1:
continue
else:
ans+=math.ceil(((a[i]-3)/2)+1)
if i>0 and a[i-1]==1:
if i<len(a)-1 and a[i+1]==1:
if a[i]%2==0:
ans+=1
print(ans)
```
No
| 94,797 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Vasya and Petya have invented a new game. Vasya takes a stripe consisting of 1 × n square and paints the squares black and white. After that Petya can start moves — during a move he may choose any two neighboring squares of one color and repaint these two squares any way he wants, perhaps in different colors. Petya can only repaint the squares in white and black colors. Petya’s aim is to repaint the stripe so that no two neighboring squares were of one color. Help Petya, using the given initial coloring, find the minimum number of moves Petya needs to win.
Input
The first line contains number n (1 ≤ n ≤ 1000) which represents the stripe’s length. The second line contains exactly n symbols — the line’s initial coloring. 0 corresponds to a white square, 1 corresponds to a black one.
Output
If Petya cannot win with such an initial coloring, print -1. Otherwise print the minimum number of moves Petya needs to win.
Examples
Input
6
111010
Output
1
Input
5
10001
Output
1
Input
7
1100010
Output
2
Input
5
00100
Output
2
Note
In the first sample Petya can take squares 1 and 2. He repaints square 1 to black and square 2 to white.
In the second sample Petya can take squares 2 and 3. He repaints square 2 to white and square 3 to black.
Submitted Solution:
```
import sys
from array import array # noqa: F401
from itertools import product
def input():
return sys.stdin.buffer.readline().decode('utf-8')
n = int(input())
s = list(map(int, input().rstrip()))
if n <= 2:
if n == 1 or s[0] != s[1]:
print(0)
else:
print(1)
exit()
inf = 10**9
dp = [inf] * 4
dp[2 * s[0] + s[1]] = 0
if s[0] == s[1]:
dp[1] = dp[2] = 1
for d in s[2:]:
next_dp = [inf] * 4
for i, j in product((0, 2), (0, 1)):
if i == j * 2:
next_dp[(j ^ 1) * 2 + d] = min(next_dp[(j ^ 1) * 2 + d], dp[i + j] + 1)
else:
next_dp[j * 2 + d] = min(next_dp[j * 2 + d], dp[i + j])
dp = next_dp
ans = min(
dp[0] + 1,
dp[1],
dp[2],
dp[3] + 1
)
print(ans if ans < inf else -1)
```
No
| 94,798 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Vasya and Petya have invented a new game. Vasya takes a stripe consisting of 1 × n square and paints the squares black and white. After that Petya can start moves — during a move he may choose any two neighboring squares of one color and repaint these two squares any way he wants, perhaps in different colors. Petya can only repaint the squares in white and black colors. Petya’s aim is to repaint the stripe so that no two neighboring squares were of one color. Help Petya, using the given initial coloring, find the minimum number of moves Petya needs to win.
Input
The first line contains number n (1 ≤ n ≤ 1000) which represents the stripe’s length. The second line contains exactly n symbols — the line’s initial coloring. 0 corresponds to a white square, 1 corresponds to a black one.
Output
If Petya cannot win with such an initial coloring, print -1. Otherwise print the minimum number of moves Petya needs to win.
Examples
Input
6
111010
Output
1
Input
5
10001
Output
1
Input
7
1100010
Output
2
Input
5
00100
Output
2
Note
In the first sample Petya can take squares 1 and 2. He repaints square 1 to black and square 2 to white.
In the second sample Petya can take squares 2 and 3. He repaints square 2 to white and square 3 to black.
Submitted Solution:
```
#Code by Sounak, IIESTS
#------------------------------warmup----------------------------
import os
import sys
import math
from io import BytesIO, IOBase
from fractions import Fraction
from collections import defaultdict
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())
s=input()
a=list()
for i in s:
a.append(int(i))
r=0
if a[0]==a[1] and n>2:
r+=1
if a[1]==a[2]:
a[1]=1-a[1]
else:
a[0]=1-a[0]
for i in range (0,n-1):
if a[i]==a[i+1]:
r+=1
a[i+1]=1-a[i+1]
print(r)
```
No
| 94,799 |
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