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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Imagine that you are in a building that has exactly n floors. You can move between the floors in a lift. Let's number the floors from bottom to top with integers from 1 to n. Now you're on the floor number a. You are very bored, so you want to take the lift. Floor number b has a secret lab, the entry is forbidden. However, you already are in the mood and decide to make k consecutive trips in the lift. Let us suppose that at the moment you are on the floor number x (initially, you were on floor a). For another trip between floors you choose some floor with number y (y ≠ x) and the lift travels to this floor. As you cannot visit floor b with the secret lab, you decided that the distance from the current floor x to the chosen y must be strictly less than the distance from the current floor x to floor b with the secret lab. Formally, it means that the following inequation must fulfill: |x - y| < |x - b|. After the lift successfully transports you to floor y, you write down number y in your notepad. Your task is to find the number of distinct number sequences that you could have written in the notebook as the result of k trips in the lift. As the sought number of trips can be rather large, find the remainder after dividing the number by 1000000007 (109 + 7). Input The first line of the input contains four space-separated integers n, a, b, k (2 ≤ n ≤ 5000, 1 ≤ k ≤ 5000, 1 ≤ a, b ≤ n, a ≠ b). Output Print a single integer — the remainder after dividing the sought number of sequences by 1000000007 (109 + 7). Examples Input 5 2 4 1 Output 2 Input 5 2 4 2 Output 2 Input 5 3 4 1 Output 0 Note Two sequences p1, p2, ..., pk and q1, q2, ..., qk are distinct, if there is such integer j (1 ≤ j ≤ k), that pj ≠ qj. Notes to the samples: 1. In the first sample after the first trip you are either on floor 1, or on floor 3, because |1 - 2| < |2 - 4| and |3 - 2| < |2 - 4|. 2. In the second sample there are two possible sequences: (1, 2); (1, 3). You cannot choose floor 3 for the first trip because in this case no floor can be the floor for the second trip. 3. In the third sample there are no sought sequences, because you cannot choose the floor for the first trip. Submitted Solution: ``` from sys import stdin #parser def parser(): return map(int, stdin.readline().split()) mod=pow(10,9)+7 n,a,b,k=parser() if a>b: a=n-a+1 n=n-b b=n+1 else: n=b-1 prefix_sum=[0 for x in range(n+1)] secuences=[0 for x in range(n+1)] secuences[a]=1 for i in range(k): prefix_sum[0]=secuences[0] for j in range(1,n+1): prefix_sum[j]=prefix_sum[j-1]+secuences[j] prefix_sum[j]%=mod for j in range(1,n+1): distance=b-j mid_distance=0 if distance % 2 == 0: mid_distance=distance//2-1 else: mid_distance=distance//2 secuences[j]=prefix_sum[j-1]+prefix_sum[j+mid_distance]-prefix_sum[j] secuences[j]%=mod print(sum(secuences)%mod) ``` Yes
90,500
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Imagine that you are in a building that has exactly n floors. You can move between the floors in a lift. Let's number the floors from bottom to top with integers from 1 to n. Now you're on the floor number a. You are very bored, so you want to take the lift. Floor number b has a secret lab, the entry is forbidden. However, you already are in the mood and decide to make k consecutive trips in the lift. Let us suppose that at the moment you are on the floor number x (initially, you were on floor a). For another trip between floors you choose some floor with number y (y ≠ x) and the lift travels to this floor. As you cannot visit floor b with the secret lab, you decided that the distance from the current floor x to the chosen y must be strictly less than the distance from the current floor x to floor b with the secret lab. Formally, it means that the following inequation must fulfill: |x - y| < |x - b|. After the lift successfully transports you to floor y, you write down number y in your notepad. Your task is to find the number of distinct number sequences that you could have written in the notebook as the result of k trips in the lift. As the sought number of trips can be rather large, find the remainder after dividing the number by 1000000007 (109 + 7). Input The first line of the input contains four space-separated integers n, a, b, k (2 ≤ n ≤ 5000, 1 ≤ k ≤ 5000, 1 ≤ a, b ≤ n, a ≠ b). Output Print a single integer — the remainder after dividing the sought number of sequences by 1000000007 (109 + 7). Examples Input 5 2 4 1 Output 2 Input 5 2 4 2 Output 2 Input 5 3 4 1 Output 0 Note Two sequences p1, p2, ..., pk and q1, q2, ..., qk are distinct, if there is such integer j (1 ≤ j ≤ k), that pj ≠ qj. Notes to the samples: 1. In the first sample after the first trip you are either on floor 1, or on floor 3, because |1 - 2| < |2 - 4| and |3 - 2| < |2 - 4|. 2. In the second sample there are two possible sequences: (1, 2); (1, 3). You cannot choose floor 3 for the first trip because in this case no floor can be the floor for the second trip. 3. In the third sample there are no sought sequences, because you cannot choose the floor for the first trip. Submitted Solution: ``` def solve(n, st, k): MOD = int(1e9 + 7) dp = [0] * (n + 1) prefix_sum = [0] * (n + 1) dp[st] = 1 for times in range(k): prefix_sum[0] = 0 for i in range(1, n + 1): prefix_sum[i] = prefix_sum[i - 1] + dp[i] if prefix_sum[i] >= MOD: prefix_sum[i] -= MOD for i in range(1, n + 1): t = prefix_sum[n] - prefix_sum[i] + prefix_sum[i - 1] - prefix_sum[i >> 1] while t < 0: t += MOD while t >= MOD: t -= MOD dp[i] = t return sum(dp) % MOD def main(): n, a, b, k = [int(i) for i in input().split()] if a > b: print(solve(n - b, a - b, k)) else: print(solve(b - 1, b - a, k)) main() ``` Yes
90,501
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Imagine that you are in a building that has exactly n floors. You can move between the floors in a lift. Let's number the floors from bottom to top with integers from 1 to n. Now you're on the floor number a. You are very bored, so you want to take the lift. Floor number b has a secret lab, the entry is forbidden. However, you already are in the mood and decide to make k consecutive trips in the lift. Let us suppose that at the moment you are on the floor number x (initially, you were on floor a). For another trip between floors you choose some floor with number y (y ≠ x) and the lift travels to this floor. As you cannot visit floor b with the secret lab, you decided that the distance from the current floor x to the chosen y must be strictly less than the distance from the current floor x to floor b with the secret lab. Formally, it means that the following inequation must fulfill: |x - y| < |x - b|. After the lift successfully transports you to floor y, you write down number y in your notepad. Your task is to find the number of distinct number sequences that you could have written in the notebook as the result of k trips in the lift. As the sought number of trips can be rather large, find the remainder after dividing the number by 1000000007 (109 + 7). Input The first line of the input contains four space-separated integers n, a, b, k (2 ≤ n ≤ 5000, 1 ≤ k ≤ 5000, 1 ≤ a, b ≤ n, a ≠ b). Output Print a single integer — the remainder after dividing the sought number of sequences by 1000000007 (109 + 7). Examples Input 5 2 4 1 Output 2 Input 5 2 4 2 Output 2 Input 5 3 4 1 Output 0 Note Two sequences p1, p2, ..., pk and q1, q2, ..., qk are distinct, if there is such integer j (1 ≤ j ≤ k), that pj ≠ qj. Notes to the samples: 1. In the first sample after the first trip you are either on floor 1, or on floor 3, because |1 - 2| < |2 - 4| and |3 - 2| < |2 - 4|. 2. In the second sample there are two possible sequences: (1, 2); (1, 3). You cannot choose floor 3 for the first trip because in this case no floor can be the floor for the second trip. 3. In the third sample there are no sought sequences, because you cannot choose the floor for the first trip. Submitted Solution: ``` n,a,b,k = map(int,input().split()) mod = 1000000007 arr = [[0 for i in range(k+1)] for j in range(n+1)] for i in range(1,n+1): if i!=b and i!=a: if abs(a-i) < abs(a-b): arr[i][1] = 1 #print(arr[2][1]) for i in range(2,k+1): for j in range(1,n+1): arr[j][i-1] = (arr[j][i-1]%mod + arr[j-1][i-1])%mod for j in range(1,n+1): if b>(j+1) and a<b: r = j+(b-j-1)//2 arr[j][i] = ((arr[r][i-1]-arr[j][i-1]) + (arr[j-1][i-1]-arr[0][i-1]))%mod elif b<(j-1) and a>b: l = j-(j-b-1)//2 arr[j][i] = ((arr[j-1][i-1]-arr[l-1][i-1]) + (arr[n][i-1]-arr[j][i-1]))%mod elif b==(j+1) and a<b: arr[j][i] = (arr[j-1][i-1]-arr[0][i-1]) elif b==(j-1) and a>b: arr[j][i] = (arr[n][i-1]-arr[j][i-1]) req = 0 for i in range(1,n+1): req = (req+arr[i][k])%mod print(req%mod) ``` Yes
90,502
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Imagine that you are in a building that has exactly n floors. You can move between the floors in a lift. Let's number the floors from bottom to top with integers from 1 to n. Now you're on the floor number a. You are very bored, so you want to take the lift. Floor number b has a secret lab, the entry is forbidden. However, you already are in the mood and decide to make k consecutive trips in the lift. Let us suppose that at the moment you are on the floor number x (initially, you were on floor a). For another trip between floors you choose some floor with number y (y ≠ x) and the lift travels to this floor. As you cannot visit floor b with the secret lab, you decided that the distance from the current floor x to the chosen y must be strictly less than the distance from the current floor x to floor b with the secret lab. Formally, it means that the following inequation must fulfill: |x - y| < |x - b|. After the lift successfully transports you to floor y, you write down number y in your notepad. Your task is to find the number of distinct number sequences that you could have written in the notebook as the result of k trips in the lift. As the sought number of trips can be rather large, find the remainder after dividing the number by 1000000007 (109 + 7). Input The first line of the input contains four space-separated integers n, a, b, k (2 ≤ n ≤ 5000, 1 ≤ k ≤ 5000, 1 ≤ a, b ≤ n, a ≠ b). Output Print a single integer — the remainder after dividing the sought number of sequences by 1000000007 (109 + 7). Examples Input 5 2 4 1 Output 2 Input 5 2 4 2 Output 2 Input 5 3 4 1 Output 0 Note Two sequences p1, p2, ..., pk and q1, q2, ..., qk are distinct, if there is such integer j (1 ≤ j ≤ k), that pj ≠ qj. Notes to the samples: 1. In the first sample after the first trip you are either on floor 1, or on floor 3, because |1 - 2| < |2 - 4| and |3 - 2| < |2 - 4|. 2. In the second sample there are two possible sequences: (1, 2); (1, 3). You cannot choose floor 3 for the first trip because in this case no floor can be the floor for the second trip. 3. In the third sample there are no sought sequences, because you cannot choose the floor for the first trip. Submitted Solution: ``` #!/usr/bin/env python3 import io import os import sys input = io.BytesIO(os.read(0,os.fstat(0).st_size)).readline def printd(*args, **kwargs): #print(*args, **kwargs, file=sys.stderr) #print(*args, **kwargs) pass def get_str(): return input().decode().strip() def rint(): return map(int, input().split()) def oint(): return int(input()) mod = 1000000007 n, a, b, k = rint() if a > b: a, b = n-a+1, n-b+1 a -= 1 b -= 1 printd(n, a, b, k) d = [0]*n d[a] = 1 ps = [0]*b ps[0] = d[0] for j in range(1, b): ps[j] = ps[j-1]+d[j] ps[j] %= mod while ps[j] > mod: ps[j] -= mod printd(n, a, b, k) printd(d, ps) for i in range(k): for j in range(b): #b-t > t-j #2*t < b+j #t < (b+j)/2 if (b+j)%2: t = (b+j)//2 else: t = (b+j)//2 - 1 if j == 0: d[j] = ps[t] - ps[j] else: d[j] = ps[t] - ps[j] + ps[j-1] d[j] %= mod while d[j] > mod: d[j] -= mod while d[j] <0: d[j] += mod #d[j] %=mod ps[0] = d[0] for j in range(1, b): ps[j] = (ps[j-1]+d[j])# %mod ps[j] %= mod while ps[j] > mod: ps[j] -= mod while ps[j] < 0: ps[j] += mod printd(d,ps) ans = ps[b-1] print(ans%mod) ``` Yes
90,503
Evaluate the correctness of the submitted Python 2 solution to the coding contest problem. Provide a "Yes" or "No" response. Imagine that you are in a building that has exactly n floors. You can move between the floors in a lift. Let's number the floors from bottom to top with integers from 1 to n. Now you're on the floor number a. You are very bored, so you want to take the lift. Floor number b has a secret lab, the entry is forbidden. However, you already are in the mood and decide to make k consecutive trips in the lift. Let us suppose that at the moment you are on the floor number x (initially, you were on floor a). For another trip between floors you choose some floor with number y (y ≠ x) and the lift travels to this floor. As you cannot visit floor b with the secret lab, you decided that the distance from the current floor x to the chosen y must be strictly less than the distance from the current floor x to floor b with the secret lab. Formally, it means that the following inequation must fulfill: |x - y| < |x - b|. After the lift successfully transports you to floor y, you write down number y in your notepad. Your task is to find the number of distinct number sequences that you could have written in the notebook as the result of k trips in the lift. As the sought number of trips can be rather large, find the remainder after dividing the number by 1000000007 (109 + 7). Input The first line of the input contains four space-separated integers n, a, b, k (2 ≤ n ≤ 5000, 1 ≤ k ≤ 5000, 1 ≤ a, b ≤ n, a ≠ b). Output Print a single integer — the remainder after dividing the sought number of sequences by 1000000007 (109 + 7). Examples Input 5 2 4 1 Output 2 Input 5 2 4 2 Output 2 Input 5 3 4 1 Output 0 Note Two sequences p1, p2, ..., pk and q1, q2, ..., qk are distinct, if there is such integer j (1 ≤ j ≤ k), that pj ≠ qj. Notes to the samples: 1. In the first sample after the first trip you are either on floor 1, or on floor 3, because |1 - 2| < |2 - 4| and |3 - 2| < |2 - 4|. 2. In the second sample there are two possible sequences: (1, 2); (1, 3). You cannot choose floor 3 for the first trip because in this case no floor can be the floor for the second trip. 3. In the third sample there are no sought sequences, because you cannot choose the floor for the first trip. Submitted Solution: ``` from sys import stdin, stdout from collections import Counter, defaultdict from itertools import permutations, combinations raw_input = stdin.readline pr = stdout.write def in_num(): return int(raw_input()) def in_arr(): return map(int,raw_input().split()) def pr_num(n): stdout.write(str(n)+'\n') def pr_arr(arr): pr(' '.join(map(str,arr))+'\n') # fast read function for total integer input def inp(): # this function returns whole input of # space/line seperated integers # Use Ctrl+D to flush stdin. return map(int,stdin.read().split()) range = xrange # not for python 3.0+ mod=10**9+7 n,a,b,k=in_arr() dp=[[0 for i in range(n+1)] for j in range(k+1)] dp[0][a-1]=1 dp[0][a]=-1 b-=1 for i in range(k): temp=0 for j in range(n+1): temp=(temp+dp[i][j])%mod if i and int(abs(b-j))>1: temp-=dp[i-1][j] temp%=mod if j<n: x=int(abs(b-j)) x-=1 if x<=0: continue dp[i+1][max(0,j-x)]=(dp[i+1][max(0,j-x)]+temp)%mod dp[i+1][min(n,j+x+1)]=(dp[i+1][min(n,j+x+1)]-temp)%mod #dp[i+1][j]=(dp[i+1][j]-1)%mod #dp[i+1][j+1]=(dp[i+1][j+1]+1)%mod if i and int(abs(b-j))>1: temp+=dp[i-1][j] temp%=mod ans=0 temp=0 for i in range(n): temp+=dp[k][i] temp%=mod if int(abs(i-b))>1: temp-=dp[k-1][i] temp%=mod ans+=temp ans%=mod if int(abs(i-b))>1: temp+=dp[k-1][i] temp%=mod pr_num(ans) ``` No
90,504
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Imagine that you are in a building that has exactly n floors. You can move between the floors in a lift. Let's number the floors from bottom to top with integers from 1 to n. Now you're on the floor number a. You are very bored, so you want to take the lift. Floor number b has a secret lab, the entry is forbidden. However, you already are in the mood and decide to make k consecutive trips in the lift. Let us suppose that at the moment you are on the floor number x (initially, you were on floor a). For another trip between floors you choose some floor with number y (y ≠ x) and the lift travels to this floor. As you cannot visit floor b with the secret lab, you decided that the distance from the current floor x to the chosen y must be strictly less than the distance from the current floor x to floor b with the secret lab. Formally, it means that the following inequation must fulfill: |x - y| < |x - b|. After the lift successfully transports you to floor y, you write down number y in your notepad. Your task is to find the number of distinct number sequences that you could have written in the notebook as the result of k trips in the lift. As the sought number of trips can be rather large, find the remainder after dividing the number by 1000000007 (109 + 7). Input The first line of the input contains four space-separated integers n, a, b, k (2 ≤ n ≤ 5000, 1 ≤ k ≤ 5000, 1 ≤ a, b ≤ n, a ≠ b). Output Print a single integer — the remainder after dividing the sought number of sequences by 1000000007 (109 + 7). Examples Input 5 2 4 1 Output 2 Input 5 2 4 2 Output 2 Input 5 3 4 1 Output 0 Note Two sequences p1, p2, ..., pk and q1, q2, ..., qk are distinct, if there is such integer j (1 ≤ j ≤ k), that pj ≠ qj. Notes to the samples: 1. In the first sample after the first trip you are either on floor 1, or on floor 3, because |1 - 2| < |2 - 4| and |3 - 2| < |2 - 4|. 2. In the second sample there are two possible sequences: (1, 2); (1, 3). You cannot choose floor 3 for the first trip because in this case no floor can be the floor for the second trip. 3. In the third sample there are no sought sequences, because you cannot choose the floor for the first trip. Submitted Solution: ``` n,a,b,k=map(int,input().split()) dp=[[0 for i in range(n+1)] for j in range(2)] dp[0][a]=1 now=1 last=0 mod=1000000007 for i in range(k): for j in range(1,n+1): d=max(abs(j-b)-1,0) if j!=n: dp[now][j+1]=(dp[last][j]+dp[now][j+1])%mod dp[now][min(j+d+1,n)]=(dp[now][min(j+d+1,n)]-dp[last][j])%mod if j!=1: dp[now][j]=(dp[now][j]-dp[last][j])%mod dp[now][max(j-d,1)]=(dp[now][max(j-d,1)]+dp[last][j])%mod for i1 in range(1,n+1): dp[now][i1]=(dp[now][i1]+dp[now][i1-1])%mod dp[last][i1]=0 aux=now now=last last=aux print(sum(dp[last])%mod) ``` No
90,505
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Imagine that you are in a building that has exactly n floors. You can move between the floors in a lift. Let's number the floors from bottom to top with integers from 1 to n. Now you're on the floor number a. You are very bored, so you want to take the lift. Floor number b has a secret lab, the entry is forbidden. However, you already are in the mood and decide to make k consecutive trips in the lift. Let us suppose that at the moment you are on the floor number x (initially, you were on floor a). For another trip between floors you choose some floor with number y (y ≠ x) and the lift travels to this floor. As you cannot visit floor b with the secret lab, you decided that the distance from the current floor x to the chosen y must be strictly less than the distance from the current floor x to floor b with the secret lab. Formally, it means that the following inequation must fulfill: |x - y| < |x - b|. After the lift successfully transports you to floor y, you write down number y in your notepad. Your task is to find the number of distinct number sequences that you could have written in the notebook as the result of k trips in the lift. As the sought number of trips can be rather large, find the remainder after dividing the number by 1000000007 (109 + 7). Input The first line of the input contains four space-separated integers n, a, b, k (2 ≤ n ≤ 5000, 1 ≤ k ≤ 5000, 1 ≤ a, b ≤ n, a ≠ b). Output Print a single integer — the remainder after dividing the sought number of sequences by 1000000007 (109 + 7). Examples Input 5 2 4 1 Output 2 Input 5 2 4 2 Output 2 Input 5 3 4 1 Output 0 Note Two sequences p1, p2, ..., pk and q1, q2, ..., qk are distinct, if there is such integer j (1 ≤ j ≤ k), that pj ≠ qj. Notes to the samples: 1. In the first sample after the first trip you are either on floor 1, or on floor 3, because |1 - 2| < |2 - 4| and |3 - 2| < |2 - 4|. 2. In the second sample there are two possible sequences: (1, 2); (1, 3). You cannot choose floor 3 for the first trip because in this case no floor can be the floor for the second trip. 3. In the third sample there are no sought sequences, because you cannot choose the floor for the first trip. Submitted Solution: ``` n,a,b,k=map(int,input().split()) dp=[[0 for i in range(n+1)] for j in range(a)] dp[0][a]=1 now=1 last=0 mod=1000000007 for i in range(k): for j in range(1,n+1): d=abs(j-b)-1 if j!=n: dp[now][j+1]=(dp[last][j]+dp[now][j+1])%mod dp[now][min(j+d+1,n)]=(dp[now][min(j+d+1,n)]+dp[last][j])%mod if j!=1: dp[now][j]=(dp[now][j]-dp[last][j])%mod dp[now][max(j-d,1)]=(dp[now][max(j-d,1)]+dp[last][j])%mod for i in range(1,n+1): dp[now][i]=(dp[now][i]+dp[now][i-1])%mod dp[last][i]=0 aux=now now=last last=aux print(sum(dp[last])%mod) ``` No
90,506
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Imagine that you are in a building that has exactly n floors. You can move between the floors in a lift. Let's number the floors from bottom to top with integers from 1 to n. Now you're on the floor number a. You are very bored, so you want to take the lift. Floor number b has a secret lab, the entry is forbidden. However, you already are in the mood and decide to make k consecutive trips in the lift. Let us suppose that at the moment you are on the floor number x (initially, you were on floor a). For another trip between floors you choose some floor with number y (y ≠ x) and the lift travels to this floor. As you cannot visit floor b with the secret lab, you decided that the distance from the current floor x to the chosen y must be strictly less than the distance from the current floor x to floor b with the secret lab. Formally, it means that the following inequation must fulfill: |x - y| < |x - b|. After the lift successfully transports you to floor y, you write down number y in your notepad. Your task is to find the number of distinct number sequences that you could have written in the notebook as the result of k trips in the lift. As the sought number of trips can be rather large, find the remainder after dividing the number by 1000000007 (109 + 7). Input The first line of the input contains four space-separated integers n, a, b, k (2 ≤ n ≤ 5000, 1 ≤ k ≤ 5000, 1 ≤ a, b ≤ n, a ≠ b). Output Print a single integer — the remainder after dividing the sought number of sequences by 1000000007 (109 + 7). Examples Input 5 2 4 1 Output 2 Input 5 2 4 2 Output 2 Input 5 3 4 1 Output 0 Note Two sequences p1, p2, ..., pk and q1, q2, ..., qk are distinct, if there is such integer j (1 ≤ j ≤ k), that pj ≠ qj. Notes to the samples: 1. In the first sample after the first trip you are either on floor 1, or on floor 3, because |1 - 2| < |2 - 4| and |3 - 2| < |2 - 4|. 2. In the second sample there are two possible sequences: (1, 2); (1, 3). You cannot choose floor 3 for the first trip because in this case no floor can be the floor for the second trip. 3. In the third sample there are no sought sequences, because you cannot choose the floor for the first trip. Submitted Solution: ``` #!/usr/bin/env python3 import io import os import sys input = io.BytesIO(os.read(0,os.fstat(0).st_size)).readline def printd(*args, **kwargs): #print(*args, **kwargs, file=sys.stderr) #print(*args, **kwargs) pass def get_str(): return input().decode().strip() def rint(): return map(int, input().split()) def oint(): return int(input()) mod = 1000000007 n, a, b, k = rint() a -= 1 b -= 1 d = [0]*n d[a] = 1 ps = [0]*n ps[0] = d[0] for j in range(1, n): ps[j] = ps[j-1]+d[j] printd(n, a, b, k) printd(d, ps) for i in range(k): d = [0]*n for j in range(1, b): d[j] = ps[j-1] for j in range(b): #b-t > t-j #2*t < b+j #t < (b+j)/2 if (b+j)%2: t = (b+j)//2 else: t = (b+j)//2 - 1 d[j] += ps[t] - ps[j] ps = [0]*n ps[0] = d[0] for j in range(1, n): ps[j] = (ps[j-1]+d[j])%mod printd(d,ps) print(ps[n-1]%mod) ``` No
90,507
Provide tags and a correct Python 3 solution for this coding contest problem. Leonid wants to become a glass carver (the person who creates beautiful artworks by cutting the glass). He already has a rectangular w mm × h mm sheet of glass, a diamond glass cutter and lots of enthusiasm. What he lacks is understanding of what to carve and how. In order not to waste time, he decided to practice the technique of carving. To do this, he makes vertical and horizontal cuts through the entire sheet. This process results in making smaller rectangular fragments of glass. Leonid does not move the newly made glass fragments. In particular, a cut divides each fragment of glass that it goes through into smaller fragments. After each cut Leonid tries to determine what area the largest of the currently available glass fragments has. Since there appear more and more fragments, this question takes him more and more time and distracts him from the fascinating process. Leonid offers to divide the labor — he will cut glass, and you will calculate the area of the maximum fragment after each cut. Do you agree? Input The first line contains three integers w, h, n (2 ≤ w, h ≤ 200 000, 1 ≤ n ≤ 200 000). Next n lines contain the descriptions of the cuts. Each description has the form H y or V x. In the first case Leonid makes the horizontal cut at the distance y millimeters (1 ≤ y ≤ h - 1) from the lower edge of the original sheet of glass. In the second case Leonid makes a vertical cut at distance x (1 ≤ x ≤ w - 1) millimeters from the left edge of the original sheet of glass. It is guaranteed that Leonid won't make two identical cuts. Output After each cut print on a single line the area of the maximum available glass fragment in mm2. Examples Input 4 3 4 H 2 V 2 V 3 V 1 Output 8 4 4 2 Input 7 6 5 H 4 V 3 V 5 H 2 V 1 Output 28 16 12 6 4 Note Picture for the first sample test: <image> Picture for the second sample test: <image> Tags: binary search, data structures, implementation Correct Solution: ``` # import itertools # import bisect # import math from collections import defaultdict, Counter import os import sys from io import BytesIO, IOBase # sys.setrecursionlimit(10 ** 5) ii = lambda: int(input()) lmii = lambda: list(map(int, input().split())) slmii = lambda: sorted(map(int, input().split())) li = lambda: list(input()) mii = lambda: map(int, input().split()) msi = lambda: map(str, input().split()) 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 gcd(a, b): if b == 0: return a return gcd(b, a % b) def lcm(a, b): return (a * b) // gcd(a, b) def main(): # for _ in " " * int(input()): w, h, n = mii() ws, dws, hs, dhs, hsm, wsm = SortedList([]), defaultdict(int), SortedList([]), defaultdict(int), SortedList( []), SortedList([]) hsm.add(h); wsm.add(w); hs.add(0); ws.add(0); hs.add(h); ws.add(w); dhs[h] = 1; dhs[0] = 1; dws[0] = 1; dws[w] = 1 for i in range(n): t, p = map(str, input().split()) p = int(p) if t == "H": if dhs[p] == 0: hs.add(p) dhs[p] = 1 ind = hs.bisect_left(p) pre, nex = hs[ind - 1], hs[ind + 1] hsm.__delitem__(hsm.bisect_left(nex - pre)); hsm.add(p - pre); hsm.add(nex - p) else: if dws[p] == 0: ws.add(p) dws[p] = 1 ind = ws.bisect_left(p) pre, nex = ws[ind - 1], ws[ind + 1] wsm.__delitem__(wsm.bisect_left(nex - pre)); wsm.add(p - pre); wsm.add(nex - p) print(wsm[-1] * hsm[-1]) pass 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") if __name__ == "__main__": main() ```
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Provide tags and a correct Python 3 solution for this coding contest problem. Leonid wants to become a glass carver (the person who creates beautiful artworks by cutting the glass). He already has a rectangular w mm × h mm sheet of glass, a diamond glass cutter and lots of enthusiasm. What he lacks is understanding of what to carve and how. In order not to waste time, he decided to practice the technique of carving. To do this, he makes vertical and horizontal cuts through the entire sheet. This process results in making smaller rectangular fragments of glass. Leonid does not move the newly made glass fragments. In particular, a cut divides each fragment of glass that it goes through into smaller fragments. After each cut Leonid tries to determine what area the largest of the currently available glass fragments has. Since there appear more and more fragments, this question takes him more and more time and distracts him from the fascinating process. Leonid offers to divide the labor — he will cut glass, and you will calculate the area of the maximum fragment after each cut. Do you agree? Input The first line contains three integers w, h, n (2 ≤ w, h ≤ 200 000, 1 ≤ n ≤ 200 000). Next n lines contain the descriptions of the cuts. Each description has the form H y or V x. In the first case Leonid makes the horizontal cut at the distance y millimeters (1 ≤ y ≤ h - 1) from the lower edge of the original sheet of glass. In the second case Leonid makes a vertical cut at distance x (1 ≤ x ≤ w - 1) millimeters from the left edge of the original sheet of glass. It is guaranteed that Leonid won't make two identical cuts. Output After each cut print on a single line the area of the maximum available glass fragment in mm2. Examples Input 4 3 4 H 2 V 2 V 3 V 1 Output 8 4 4 2 Input 7 6 5 H 4 V 3 V 5 H 2 V 1 Output 28 16 12 6 4 Note Picture for the first sample test: <image> Picture for the second sample test: <image> Tags: binary search, data structures, implementation Correct Solution: ``` w,h,n=map(int,input().split()) l=[-1]*(w+1) r=[-1]*(w+1) t=[-1]*(h+1) b=[-1]*(h+1) l[0]=0 b[0]=0 t[h]=h r[w]=w V=[0]*(n) H=[0]*(n) for i in range(n): line,index=input().split() index=int(index) if line=="V": r[index]=w V[i]=index else: t[index]=h H[i]=index left=0 mxw=0 for i in range(1,w+1): if r[i]!=-1: l[i]=left r[left]=i mxw=max(mxw,i-left) left=i bottom=0 mxh=0 for i in range(1,h+1): if t[i]!=-1: b[i]=bottom t[bottom]=i mxh=max(mxh,i-bottom) bottom=i ans=[0]*(n) ans[n-1]=mxh*mxw for i in range(n-1,0,-1): if V[i]!=0: mxw=max(mxw,r[V[i]]-l[V[i]]) r[l[V[i]]]=r[V[i]] l[r[V[i]]]=l[V[i]] else: mxh=max(mxh,t[H[i]]-b[H[i]]) b[t[H[i]]]=b[H[i]] t[b[H[i]]]=t[H[i]] ans[i-1]=mxh*mxw for i in range(n): print(ans[i]) ```
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Provide tags and a correct Python 3 solution for this coding contest problem. Leonid wants to become a glass carver (the person who creates beautiful artworks by cutting the glass). He already has a rectangular w mm × h mm sheet of glass, a diamond glass cutter and lots of enthusiasm. What he lacks is understanding of what to carve and how. In order not to waste time, he decided to practice the technique of carving. To do this, he makes vertical and horizontal cuts through the entire sheet. This process results in making smaller rectangular fragments of glass. Leonid does not move the newly made glass fragments. In particular, a cut divides each fragment of glass that it goes through into smaller fragments. After each cut Leonid tries to determine what area the largest of the currently available glass fragments has. Since there appear more and more fragments, this question takes him more and more time and distracts him from the fascinating process. Leonid offers to divide the labor — he will cut glass, and you will calculate the area of the maximum fragment after each cut. Do you agree? Input The first line contains three integers w, h, n (2 ≤ w, h ≤ 200 000, 1 ≤ n ≤ 200 000). Next n lines contain the descriptions of the cuts. Each description has the form H y or V x. In the first case Leonid makes the horizontal cut at the distance y millimeters (1 ≤ y ≤ h - 1) from the lower edge of the original sheet of glass. In the second case Leonid makes a vertical cut at distance x (1 ≤ x ≤ w - 1) millimeters from the left edge of the original sheet of glass. It is guaranteed that Leonid won't make two identical cuts. Output After each cut print on a single line the area of the maximum available glass fragment in mm2. Examples Input 4 3 4 H 2 V 2 V 3 V 1 Output 8 4 4 2 Input 7 6 5 H 4 V 3 V 5 H 2 V 1 Output 28 16 12 6 4 Note Picture for the first sample test: <image> Picture for the second sample test: <image> Tags: binary search, data structures, implementation Correct Solution: ``` # -*- coding:utf-8 -*- """ created by shuangquan.huang at 1/7/20 reverse thinking of merging instead of split """ import collections import time import os import sys import bisect import heapq from typing import List class Node: val = None def __init__(self, val): self.val = val self.left = Node self.right = None def solve(W, H, N, A): xs = [0] + [v for t, v in A if t == 0] + [W] ys = [0] + [v for t, v in A if t == 1] + [H] xs.sort() ys.sort() xlist = Node(0) h = xlist xnodes = {0: h} maxw = max([xs[i+1] - xs[i] for i in range(len(xs)-1)] or [0]) maxh = max([ys[i+1] - ys[i] for i in range(len(ys)-1)] or [0]) for v in xs[1:]: n = Node(v) xnodes[v] = n h.right = n n.left = h h = n ylist = Node(0) h = ylist ynodes = {0: h} for v in ys[1:]: n = Node(v) ynodes[v] = n h.right = n n.left = h h = n ans = [] maxarea = maxh * maxw for t, v in reversed(A): ans.append(maxarea) if t == 0: node = xnodes[v] w = node.right.val - node.left.val maxw = max(maxw, w) else: node = ynodes[v] h = node.right.val - node.left.val maxh = max(maxh, h) node.left.right = node.right node.right.left = node.left maxarea = maxh * maxw return ans[::-1] def solve2(W, H, N, A): ws = [(-W, 0, W)] hs = [(-H, 0, H)] iw, ih = set(), set() ans = [] xs, ys = [0, W], [0, H] for t, v in A: if t == 0: bisect.insort_left(xs, v) i = bisect.bisect_left(xs, v) l, m, r = xs[i-1], xs[i], xs[i+1] iw.add((l-r, l, r)) heapq.heappush(ws, (l - m, l, m)) heapq.heappush(ws, (m - r, m, r)) while ws[0] in iw: heapq.heappop(ws) else: bisect.insort(ys, v) i = bisect.bisect_left(ys, v) l, m, r = ys[i-1], ys[i], ys[i+1] ih.add((l-r, l, r)) heapq.heappush(hs, (l - m, l, m)) heapq.heappush(hs, (m - r, m, r)) while hs[0] in ih: heapq.heappop(hs) w, h = ws[0], hs[0] ans.append(w[0] * h[0]) return ans W, H, N = map(int,input().split()) A = [] for i in range(N): a, b = input().split() c = 0 if a == 'V' else 1 A.append((c, int(b))) print('\n'.join(map(str, solve(W, H, N, A)))) ```
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Provide tags and a correct Python 3 solution for this coding contest problem. Leonid wants to become a glass carver (the person who creates beautiful artworks by cutting the glass). He already has a rectangular w mm × h mm sheet of glass, a diamond glass cutter and lots of enthusiasm. What he lacks is understanding of what to carve and how. In order not to waste time, he decided to practice the technique of carving. To do this, he makes vertical and horizontal cuts through the entire sheet. This process results in making smaller rectangular fragments of glass. Leonid does not move the newly made glass fragments. In particular, a cut divides each fragment of glass that it goes through into smaller fragments. After each cut Leonid tries to determine what area the largest of the currently available glass fragments has. Since there appear more and more fragments, this question takes him more and more time and distracts him from the fascinating process. Leonid offers to divide the labor — he will cut glass, and you will calculate the area of the maximum fragment after each cut. Do you agree? Input The first line contains three integers w, h, n (2 ≤ w, h ≤ 200 000, 1 ≤ n ≤ 200 000). Next n lines contain the descriptions of the cuts. Each description has the form H y or V x. In the first case Leonid makes the horizontal cut at the distance y millimeters (1 ≤ y ≤ h - 1) from the lower edge of the original sheet of glass. In the second case Leonid makes a vertical cut at distance x (1 ≤ x ≤ w - 1) millimeters from the left edge of the original sheet of glass. It is guaranteed that Leonid won't make two identical cuts. Output After each cut print on a single line the area of the maximum available glass fragment in mm2. Examples Input 4 3 4 H 2 V 2 V 3 V 1 Output 8 4 4 2 Input 7 6 5 H 4 V 3 V 5 H 2 V 1 Output 28 16 12 6 4 Note Picture for the first sample test: <image> Picture for the second sample test: <image> Tags: binary search, data structures, implementation Correct Solution: ``` w, h, n = map(int, input().split()) x = [0, w] y = [0, h] rev = [] for _ in range(n): s, d = input().split() if s == 'H': y.append(int(d)) else: x.append(int(d)) rev.append((s, int(d))) x.sort() y.sort() _max = 0 if len(x) > 1: for idx in range(len(x) - 1): _max = max(_max, x[idx + 1] - x[idx]) else: _max = w max_x = _max _max = 0 if len(y) > 1: for idx in range(len(y) - 1): _max = max(_max, y[idx + 1] - y[idx]) else: _max = w max_y = _max enum_x = {num : idx for idx, num in enumerate(x)} enum_y = {num : idx for idx, num in enumerate(y)} old_x = x old_y = y x = [[0, 0, 0]] * len(old_x) y = [[0, 0, 0]] * len(old_y) for idx in range(1, len(x) - 1): x[idx] = [old_x[idx], idx-1, idx+1] for idx in range(1, len(y) - 1): y[idx] = [old_y[idx], idx-1, idx+1] x[-1] = [w, 0, 0] y[-1] = [h, 0, 0] rev.reverse() ans = [max_x * max_y] for item in rev: if item[0] == 'H': elem = y[enum_y[item[1]]] max_y = max(max_y, y[elem[2]][0] - y[elem[1]][0]) y[elem[1]][2] = elem[2] y[elem[2]][1] = elem[1] else: elem = x[enum_x[item[1]]] max_x = max(max_x, x[elem[2]][0] - x[elem[1]][0]) x[elem[1]][2] = elem[2] x[elem[2]][1] = elem[1] ans.append(max_x * max_y) ans.pop() print('\n'.join(map(str, reversed(ans)))) ```
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Provide tags and a correct Python 3 solution for this coding contest problem. Leonid wants to become a glass carver (the person who creates beautiful artworks by cutting the glass). He already has a rectangular w mm × h mm sheet of glass, a diamond glass cutter and lots of enthusiasm. What he lacks is understanding of what to carve and how. In order not to waste time, he decided to practice the technique of carving. To do this, he makes vertical and horizontal cuts through the entire sheet. This process results in making smaller rectangular fragments of glass. Leonid does not move the newly made glass fragments. In particular, a cut divides each fragment of glass that it goes through into smaller fragments. After each cut Leonid tries to determine what area the largest of the currently available glass fragments has. Since there appear more and more fragments, this question takes him more and more time and distracts him from the fascinating process. Leonid offers to divide the labor — he will cut glass, and you will calculate the area of the maximum fragment after each cut. Do you agree? Input The first line contains three integers w, h, n (2 ≤ w, h ≤ 200 000, 1 ≤ n ≤ 200 000). Next n lines contain the descriptions of the cuts. Each description has the form H y or V x. In the first case Leonid makes the horizontal cut at the distance y millimeters (1 ≤ y ≤ h - 1) from the lower edge of the original sheet of glass. In the second case Leonid makes a vertical cut at distance x (1 ≤ x ≤ w - 1) millimeters from the left edge of the original sheet of glass. It is guaranteed that Leonid won't make two identical cuts. Output After each cut print on a single line the area of the maximum available glass fragment in mm2. Examples Input 4 3 4 H 2 V 2 V 3 V 1 Output 8 4 4 2 Input 7 6 5 H 4 V 3 V 5 H 2 V 1 Output 28 16 12 6 4 Note Picture for the first sample test: <image> Picture for the second sample test: <image> Tags: binary search, data structures, implementation Correct Solution: ``` def main(): from sys import stdin w, h, n = map(int, stdin.readline().split()) res, vrt, hor = [], [], [] vh = (vrt, hor) for i, s in enumerate(stdin.read().splitlines()): x = int(s[2:]) flag = s[0] == 'V' vh[flag].append(i) res.append([x, flag]) dim = [] for tmp, m in zip(vh, (h, w)): tmp.sort(key=lambda e: res[e][0]) u = [None, [0]] dim.append(u) j = z = 0 for i in tmp: x = res[i][0] if z < x - j: z = x - j j = x v = [u, res[i]] u.append(v) u = v res[i].append(u) v = [u, [m], None] u.append(v) dim.append(v) if z < m - j: z = m - j dim.append(z) l, r, wmax, u, d, hmax = dim whmax = [wmax, hmax] for i in range(n - 1, -1, -1): x, flag, link = res[i] u = whmax[flag] res[i] = u * whmax[not flag] link[0][2] = link[2] link[2][0] = link[0] v = link[2][1][0] - link[0][1][0] if u < v: whmax[flag] = v print('\n'.join(map(str, res))) if __name__ == '__main__': main() ```
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Provide tags and a correct Python 3 solution for this coding contest problem. Leonid wants to become a glass carver (the person who creates beautiful artworks by cutting the glass). He already has a rectangular w mm × h mm sheet of glass, a diamond glass cutter and lots of enthusiasm. What he lacks is understanding of what to carve and how. In order not to waste time, he decided to practice the technique of carving. To do this, he makes vertical and horizontal cuts through the entire sheet. This process results in making smaller rectangular fragments of glass. Leonid does not move the newly made glass fragments. In particular, a cut divides each fragment of glass that it goes through into smaller fragments. After each cut Leonid tries to determine what area the largest of the currently available glass fragments has. Since there appear more and more fragments, this question takes him more and more time and distracts him from the fascinating process. Leonid offers to divide the labor — he will cut glass, and you will calculate the area of the maximum fragment after each cut. Do you agree? Input The first line contains three integers w, h, n (2 ≤ w, h ≤ 200 000, 1 ≤ n ≤ 200 000). Next n lines contain the descriptions of the cuts. Each description has the form H y or V x. In the first case Leonid makes the horizontal cut at the distance y millimeters (1 ≤ y ≤ h - 1) from the lower edge of the original sheet of glass. In the second case Leonid makes a vertical cut at distance x (1 ≤ x ≤ w - 1) millimeters from the left edge of the original sheet of glass. It is guaranteed that Leonid won't make two identical cuts. Output After each cut print on a single line the area of the maximum available glass fragment in mm2. Examples Input 4 3 4 H 2 V 2 V 3 V 1 Output 8 4 4 2 Input 7 6 5 H 4 V 3 V 5 H 2 V 1 Output 28 16 12 6 4 Note Picture for the first sample test: <image> Picture for the second sample test: <image> Tags: binary search, data structures, implementation Correct Solution: ``` def main(): from sys import stdin w, h, n = map(int, stdin.readline().split()) res, vrt, hor = [], [], [] vh = (vrt, hor) for i, s in enumerate(stdin.read().splitlines()): x = int(s[2:]) flag = s[0] == 'V' vh[flag].append(i) res.append([x, flag]) dim = [] for tmp, m in zip(vh, (h, w)): tmp.sort(key=lambda e: res[e][0]) u = [None, [0]] dim.append(u) j = z = 0 for i in tmp: x = res[i][0] if z < x - j: z = x - j j = x v = [u, res[i]] u.append(v) u = v res[i].append(u) v = [u, [m], None] u.append(v) dim.append(v) if z < m - j: z = m - j dim.append(z) l, r, wmax, u, d, hmax = dim s = str(wmax * hmax) for i in range(n - 1, -1, -1): x, flag, link = res[i] u = hmax if flag else wmax res[i] = s link[0][2] = link[2] link[2][0] = link[0] v = link[2][1][0] - link[0][1][0] if u < v: if flag: hmax = v else: wmax = v s = str(wmax * hmax) print('\n'.join(res)) if __name__ == '__main__': main() ```
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Leonid wants to become a glass carver (the person who creates beautiful artworks by cutting the glass). He already has a rectangular w mm × h mm sheet of glass, a diamond glass cutter and lots of enthusiasm. What he lacks is understanding of what to carve and how. In order not to waste time, he decided to practice the technique of carving. To do this, he makes vertical and horizontal cuts through the entire sheet. This process results in making smaller rectangular fragments of glass. Leonid does not move the newly made glass fragments. In particular, a cut divides each fragment of glass that it goes through into smaller fragments. After each cut Leonid tries to determine what area the largest of the currently available glass fragments has. Since there appear more and more fragments, this question takes him more and more time and distracts him from the fascinating process. Leonid offers to divide the labor — he will cut glass, and you will calculate the area of the maximum fragment after each cut. Do you agree? Input The first line contains three integers w, h, n (2 ≤ w, h ≤ 200 000, 1 ≤ n ≤ 200 000). Next n lines contain the descriptions of the cuts. Each description has the form H y or V x. In the first case Leonid makes the horizontal cut at the distance y millimeters (1 ≤ y ≤ h - 1) from the lower edge of the original sheet of glass. In the second case Leonid makes a vertical cut at distance x (1 ≤ x ≤ w - 1) millimeters from the left edge of the original sheet of glass. It is guaranteed that Leonid won't make two identical cuts. Output After each cut print on a single line the area of the maximum available glass fragment in mm2. Examples Input 4 3 4 H 2 V 2 V 3 V 1 Output 8 4 4 2 Input 7 6 5 H 4 V 3 V 5 H 2 V 1 Output 28 16 12 6 4 Note Picture for the first sample test: <image> Picture for the second sample test: <image> Submitted Solution: ``` w,h,n=map(int,input().split()) l=[-1]*(w+1) r=[-1]*(w+1) t=[-1]*(h+1) b=[-1]*(h+1) l[0]=0 b[0]=0 V=[0]*(n) H=[0]*(n) for i in range(n): line,index=input().split() index=int(index) if line=="V": r[index]=w V[i]=index else: t[index]=h H[i]=index left=0 mxw=0 for i in range(1,w+1): if r[i]!=-1: l[i]=left r[left]=i mxw=max(mxw,i-left) left=i bottom=0 mxh=0 for i in range(1,h+1): if t[i]!=-1: b[i]=bottom t[bottom]=i mxh=max(mxh,i-bottom) bottom=i ans=[0]*(n) ans[n-1]=mxh*mxw for i in range(n-1,0,-1): if H[i]==0: mxw=max(mxw,r[V[i]]-l[V[i]]) r[l[V[i]]]=r[V[i]] l[r[V[i]]]=l[V[i]] else: mxh=max(mxh,t[H[i]]-b[H[i]]) b[t[H[i]]]=b[H[i]] t[b[H[i]]]=t[H[i]] ans[i-1]=mxh*mxw for i in range(n): print(ans[i]) ``` No
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Provide tags and a correct Python 3 solution for this coding contest problem. Kyoya Ootori has a bag with n colored balls that are colored with k different colors. The colors are labeled from 1 to k. Balls of the same color are indistinguishable. He draws balls from the bag one by one until the bag is empty. He noticed that he drew the last ball of color i before drawing the last ball of color i + 1 for all i from 1 to k - 1. Now he wonders how many different ways this can happen. Input The first line of input will have one integer k (1 ≤ k ≤ 1000) the number of colors. Then, k lines will follow. The i-th line will contain ci, the number of balls of the i-th color (1 ≤ ci ≤ 1000). The total number of balls doesn't exceed 1000. Output A single integer, the number of ways that Kyoya can draw the balls from the bag as described in the statement, modulo 1 000 000 007. Examples Input 3 2 2 1 Output 3 Input 4 1 2 3 4 Output 1680 Note In the first sample, we have 2 balls of color 1, 2 balls of color 2, and 1 ball of color 3. The three ways for Kyoya are: 1 2 1 2 3 1 1 2 2 3 2 1 1 2 3 Tags: combinatorics, dp, math Correct Solution: ``` ans, col, mod = 1, 0, 1000000007 C = [[1 if i <= j else 0 for i in range(1001)] for j in range(1001)] for i in range(1, 1001): for j in range(1, i + 1): C[i][j] = (C[i - 1][j - 1] + C[i - 1][j]) % mod for _ in range(int(input())): a = int(input()) ans *= C[col + a - 1][col] ans %= mod col += a print(ans) ```
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Provide tags and a correct Python 3 solution for this coding contest problem. Kyoya Ootori has a bag with n colored balls that are colored with k different colors. The colors are labeled from 1 to k. Balls of the same color are indistinguishable. He draws balls from the bag one by one until the bag is empty. He noticed that he drew the last ball of color i before drawing the last ball of color i + 1 for all i from 1 to k - 1. Now he wonders how many different ways this can happen. Input The first line of input will have one integer k (1 ≤ k ≤ 1000) the number of colors. Then, k lines will follow. The i-th line will contain ci, the number of balls of the i-th color (1 ≤ ci ≤ 1000). The total number of balls doesn't exceed 1000. Output A single integer, the number of ways that Kyoya can draw the balls from the bag as described in the statement, modulo 1 000 000 007. Examples Input 3 2 2 1 Output 3 Input 4 1 2 3 4 Output 1680 Note In the first sample, we have 2 balls of color 1, 2 balls of color 2, and 1 ball of color 3. The three ways for Kyoya are: 1 2 1 2 3 1 1 2 2 3 2 1 1 2 3 Tags: combinatorics, dp, math Correct Solution: ``` mx=1001 mod=1000000007 nCr=[[0 for i in range(mx)] for j in range(mx)] nCr[0][0]=1 for i in range(1,mx): nCr[i][0]=1 for j in range(1,mx): nCr[i][j]=nCr[i-1][j-1]+nCr[i-1][j] n=int(input()) l=[] for i in range(n): l.append(int(input())) res=1 total=0 for i in range(n): res=(res*nCr[total+l[i]-1][l[i]-1])%mod total+=l[i] print(res) ```
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Provide tags and a correct Python 3 solution for this coding contest problem. Kyoya Ootori has a bag with n colored balls that are colored with k different colors. The colors are labeled from 1 to k. Balls of the same color are indistinguishable. He draws balls from the bag one by one until the bag is empty. He noticed that he drew the last ball of color i before drawing the last ball of color i + 1 for all i from 1 to k - 1. Now he wonders how many different ways this can happen. Input The first line of input will have one integer k (1 ≤ k ≤ 1000) the number of colors. Then, k lines will follow. The i-th line will contain ci, the number of balls of the i-th color (1 ≤ ci ≤ 1000). The total number of balls doesn't exceed 1000. Output A single integer, the number of ways that Kyoya can draw the balls from the bag as described in the statement, modulo 1 000 000 007. Examples Input 3 2 2 1 Output 3 Input 4 1 2 3 4 Output 1680 Note In the first sample, we have 2 balls of color 1, 2 balls of color 2, and 1 ball of color 3. The three ways for Kyoya are: 1 2 1 2 3 1 1 2 2 3 2 1 1 2 3 Tags: combinatorics, dp, math Correct Solution: ``` from math import factorial k=int(input()) ans,s=1,0 for i in range(k): ci=int(input()) ans=(ans*factorial(s+ci-1)//(factorial(ci-1)*factorial(s)))%1000000007 s+=ci print(ans) ```
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Provide tags and a correct Python 3 solution for this coding contest problem. Kyoya Ootori has a bag with n colored balls that are colored with k different colors. The colors are labeled from 1 to k. Balls of the same color are indistinguishable. He draws balls from the bag one by one until the bag is empty. He noticed that he drew the last ball of color i before drawing the last ball of color i + 1 for all i from 1 to k - 1. Now he wonders how many different ways this can happen. Input The first line of input will have one integer k (1 ≤ k ≤ 1000) the number of colors. Then, k lines will follow. The i-th line will contain ci, the number of balls of the i-th color (1 ≤ ci ≤ 1000). The total number of balls doesn't exceed 1000. Output A single integer, the number of ways that Kyoya can draw the balls from the bag as described in the statement, modulo 1 000 000 007. Examples Input 3 2 2 1 Output 3 Input 4 1 2 3 4 Output 1680 Note In the first sample, we have 2 balls of color 1, 2 balls of color 2, and 1 ball of color 3. The three ways for Kyoya are: 1 2 1 2 3 1 1 2 2 3 2 1 1 2 3 Tags: combinatorics, dp, math Correct Solution: ``` from sys import stdin n=int(stdin.readline()) from math import factorial as f lst=[int(stdin.readline()) for _ in range(n)] summa=sum(lst) res=1 for i,x in enumerate(reversed(lst)): x-=1 summa-=1 res*=(f(summa)//(f(summa-x)*f(x))) res=res%1000000007 summa-=x print(res) ```
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Provide tags and a correct Python 3 solution for this coding contest problem. Kyoya Ootori has a bag with n colored balls that are colored with k different colors. The colors are labeled from 1 to k. Balls of the same color are indistinguishable. He draws balls from the bag one by one until the bag is empty. He noticed that he drew the last ball of color i before drawing the last ball of color i + 1 for all i from 1 to k - 1. Now he wonders how many different ways this can happen. Input The first line of input will have one integer k (1 ≤ k ≤ 1000) the number of colors. Then, k lines will follow. The i-th line will contain ci, the number of balls of the i-th color (1 ≤ ci ≤ 1000). The total number of balls doesn't exceed 1000. Output A single integer, the number of ways that Kyoya can draw the balls from the bag as described in the statement, modulo 1 000 000 007. Examples Input 3 2 2 1 Output 3 Input 4 1 2 3 4 Output 1680 Note In the first sample, we have 2 balls of color 1, 2 balls of color 2, and 1 ball of color 3. The three ways for Kyoya are: 1 2 1 2 3 1 1 2 2 3 2 1 1 2 3 Tags: combinatorics, dp, math Correct Solution: ``` mod = 1000000007 def pow1(a,b): ans = 1 c=a while(b): #print('estoy en el while') if(b & 1): ans=ans*c%mod b>>=1 c=c*c%mod return ans def factorial(a,b): factor =fact[a]*pow1(fact[b]*fact[a-b]%mod,mod-2)%mod return factor fact = [] for i in range(1000010): fact.append(0) a = [] for i in range(1010): a.append(0) #================MAIN=============== fact[0] = 1 for i in range(1,1000000): fact[i]=fact[i-1]*i%mod n = int(input()) #print(n) sum = 0 for i in range(0,n): a[i] = int(input()) sum+=a[i] #print (a) #print(sum) ans = 1 i = n-1 while(i>-1): ans=ans*factorial(sum-1,a[i]-1)%mod #print(ans) sum-=a[i] i-=1 #print(f"suma:{sum}") print(ans) ```
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Provide tags and a correct Python 3 solution for this coding contest problem. Kyoya Ootori has a bag with n colored balls that are colored with k different colors. The colors are labeled from 1 to k. Balls of the same color are indistinguishable. He draws balls from the bag one by one until the bag is empty. He noticed that he drew the last ball of color i before drawing the last ball of color i + 1 for all i from 1 to k - 1. Now he wonders how many different ways this can happen. Input The first line of input will have one integer k (1 ≤ k ≤ 1000) the number of colors. Then, k lines will follow. The i-th line will contain ci, the number of balls of the i-th color (1 ≤ ci ≤ 1000). The total number of balls doesn't exceed 1000. Output A single integer, the number of ways that Kyoya can draw the balls from the bag as described in the statement, modulo 1 000 000 007. Examples Input 3 2 2 1 Output 3 Input 4 1 2 3 4 Output 1680 Note In the first sample, we have 2 balls of color 1, 2 balls of color 2, and 1 ball of color 3. The three ways for Kyoya are: 1 2 1 2 3 1 1 2 2 3 2 1 1 2 3 Tags: combinatorics, dp, math Correct Solution: ``` # Author : nitish420 -------------------------------------------------------------------- import os import sys from io import BytesIO, IOBase mod=10**9+7 # sys.setrecursionlimit(10**6) # mxm=sys.maxsize # from functools import lru_cache fact=[1]*(1002) for i in range(2,1002): fact[i]=(fact[i-1]*i)%mod def ncr(n,r): num=fact[n] den=(fact[n-r]*fact[r])%mod return (num*(pow(den,mod-2,mod)))%mod def main(): k=int(input()) dp=[0]*(k+1) dp[1]=1 dff=0 m=int(input()) total=m for i in range(k-1): m=int(input()) dff=m-1 total+=m dp[i+2]=(dp[i+1]*ncr(total-1,dff))%mod print(dp[k]) #---------------------------------------------------------------------------------------- def nouse0(): # This is to save my code from plag due to use of FAST IO template in it. a=420 b=420 print(f'i am nitish{(a+b)//2}') def nouse1(): # This is to save my code from plag due to use of FAST IO template in it. a=420 b=420 print(f'i am nitish{(a+b)//2}') def nouse2(): # This is to save my code from plag due to use of FAST IO template in it. a=420 b=420 print(f'i am nitish{(a+b)//2}') # region fastio BUFSIZE = 8192 class FastIO(IOBase): newlines = 0 def __init__(self, file): self._fd = file.fileno() self.buffer = BytesIO() self.writable = 'x' in file.mode or 'r' not in file.mode self.write = self.buffer.write if self.writable else None def read(self): while True: b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE)) if not b: break ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines = 0 return self.buffer.read() def readline(self): while self.newlines == 0: b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE)) self.newlines = b.count(b'\n') + (not b) ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines -= 1 return self.buffer.readline() def flush(self): if self.writable: os.write(self._fd, self.buffer.getvalue()) self.buffer.truncate(0), self.buffer.seek(0) class IOWrapper(IOBase): def __init__(self, file): self.buffer = FastIO(file) self.flush = self.buffer.flush self.writable = self.buffer.writable self.write = lambda s: self.buffer.write(s.encode('ascii')) self.read = lambda: self.buffer.read().decode('ascii') self.readline = lambda: self.buffer.readline().decode('ascii') sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout) input = lambda: sys.stdin.readline().rstrip('\r\n') # endregion if __name__ == '__main__': main() ```
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Provide tags and a correct Python 3 solution for this coding contest problem. Kyoya Ootori has a bag with n colored balls that are colored with k different colors. The colors are labeled from 1 to k. Balls of the same color are indistinguishable. He draws balls from the bag one by one until the bag is empty. He noticed that he drew the last ball of color i before drawing the last ball of color i + 1 for all i from 1 to k - 1. Now he wonders how many different ways this can happen. Input The first line of input will have one integer k (1 ≤ k ≤ 1000) the number of colors. Then, k lines will follow. The i-th line will contain ci, the number of balls of the i-th color (1 ≤ ci ≤ 1000). The total number of balls doesn't exceed 1000. Output A single integer, the number of ways that Kyoya can draw the balls from the bag as described in the statement, modulo 1 000 000 007. Examples Input 3 2 2 1 Output 3 Input 4 1 2 3 4 Output 1680 Note In the first sample, we have 2 balls of color 1, 2 balls of color 2, and 1 ball of color 3. The three ways for Kyoya are: 1 2 1 2 3 1 1 2 2 3 2 1 1 2 3 Tags: combinatorics, dp, math Correct Solution: ``` """ Author - Satwik Tiwari . 4th Oct , 2020 - Sunday """ #=============================================================================================== #importing some useful libraries. from __future__ import division, print_function from fractions import Fraction import sys import os from io import BytesIO, IOBase # from itertools import * from heapq import * from math import gcd, factorial,floor,ceil from copy import deepcopy from collections import deque # from collections import Counter as counter # Counter(list) return a dict with {key: count} # from itertools import combinations as comb # if a = [1,2,3] then print(list(comb(a,2))) -----> [(1, 2), (1, 3), (2, 3)] # from itertools import permutations as permutate from bisect import bisect_left as bl from bisect import bisect_right as br from bisect import bisect #============================================================================================== #fast I/O region BUFSIZE = 8192 class FastIO(IOBase): newlines = 0 def __init__(self, file): self._fd = file.fileno() self.buffer = BytesIO() self.writable = "x" in file.mode or "r" not in file.mode self.write = self.buffer.write if self.writable else None def read(self): while True: b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE)) if not b: break ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines = 0 return self.buffer.read() def readline(self): while self.newlines == 0: b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE)) self.newlines = b.count(b"\n") + (not b) ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines -= 1 return self.buffer.readline() def flush(self): if self.writable: os.write(self._fd, self.buffer.getvalue()) self.buffer.truncate(0), self.buffer.seek(0) class IOWrapper(IOBase): def __init__(self, file): self.buffer = FastIO(file) self.flush = self.buffer.flush self.writable = self.buffer.writable self.write = lambda s: self.buffer.write(s.encode("ascii")) self.read = lambda: self.buffer.read().decode("ascii") self.readline = lambda: self.buffer.readline().decode("ascii") def print(*args, **kwargs): """Prints the values to a stream, or to sys.stdout by default.""" sep, file = kwargs.pop("sep", " "), kwargs.pop("file", sys.stdout) at_start = True for x in args: if not at_start: file.write(sep) file.write(str(x)) at_start = False file.write(kwargs.pop("end", "\n")) if kwargs.pop("flush", False): file.flush() if sys.version_info[0] < 3: sys.stdin, sys.stdout = FastIO(sys.stdin), FastIO(sys.stdout) else: sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout) # inp = lambda: sys.stdin.readline().rstrip("\r\n") #=============================================================================================== ### START ITERATE RECURSION ### from types import GeneratorType def iterative(f, stack=[]): def wrapped_func(*args, **kwargs): if stack: return f(*args, **kwargs) to = f(*args, **kwargs) while True: if type(to) is GeneratorType: stack.append(to) to = next(to) continue stack.pop() if not stack: break to = stack[-1].send(to) return to return wrapped_func #### END ITERATE RECURSION #### #=============================================================================================== #some shortcuts mod = 10**9+7 def inp(): return sys.stdin.readline().rstrip("\r\n") #for fast input def out(var): sys.stdout.write(str(var)) #for fast output, always take string def lis(): return list(map(int, inp().split())) def stringlis(): return list(map(str, inp().split())) def sep(): return map(int, inp().split()) def strsep(): return map(str, inp().split()) # def graph(vertex): return [[] for i in range(0,vertex+1)] def zerolist(n): return [0]*n def nextline(): out("\n") #as stdout.write always print sring. def testcase(t): for pp in range(t): solve(pp) def printlist(a) : for p in range(0,len(a)): out(str(a[p]) + ' ') def google(p): print('Case #'+str(p)+': ',end='') def lcm(a,b): return (a*b)//gcd(a,b) def power(x, y, p) : res = 1 # Initialize result x = x % p # Update x if it is more , than or equal to p if (x == 0) : return 0 while (y > 0) : if ((y & 1) == 1) : # If y is odd, multiply, x with result res = (res * x) % p y = y >> 1 # y = y/2 x = (x * x) % p return res def ncr(n,r): return factorial(n) // (factorial(r) * factorial(max(n - r, 1))) def isPrime(n) : if (n <= 1) : return False if (n <= 3) : return True if (n % 2 == 0 or n % 3 == 0) : return False i = 5 while(i * i <= n) : if (n % i == 0 or n % (i + 2) == 0) : return False i = i + 6 return True #=============================================================================================== # code here ;)) def nCr_mod(n,r,max_n=2 * 10**5, mod=10**9 + 7): max_n = min(max_n, mod - 1) fact, inv_fact = [0] * (max_n + 1), [0] * (max_n + 1) fact[0] = 1 for i in range(max_n): fact[i + 1] = fact[i] * (i + 1) % mod inv_fact[-1] = pow(fact[-1], mod - 2, mod) for i in reversed(range(max_n)): inv_fact[i] = inv_fact[i + 1] * (i + 1) % mod def do_nCr_mod(n, r): res = 1 while n or r: a, b = n % mod, r % mod if a < b: return 0 res = res * fact[a] % mod * inv_fact[b] % mod * inv_fact[a - b] % mod n //= mod r //= mod return res return do_nCr_mod(n,r) """ print nCr(4,3) """ def solve(case): n = int(inp()) ans = 1 total = 0 for i in range(n): x = int(inp()) total+= x ans*=ncr(total-1,x-1)%mod print(ans%mod) testcase(1) # testcase(int(inp())) ```
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Provide tags and a correct Python 3 solution for this coding contest problem. Kyoya Ootori has a bag with n colored balls that are colored with k different colors. The colors are labeled from 1 to k. Balls of the same color are indistinguishable. He draws balls from the bag one by one until the bag is empty. He noticed that he drew the last ball of color i before drawing the last ball of color i + 1 for all i from 1 to k - 1. Now he wonders how many different ways this can happen. Input The first line of input will have one integer k (1 ≤ k ≤ 1000) the number of colors. Then, k lines will follow. The i-th line will contain ci, the number of balls of the i-th color (1 ≤ ci ≤ 1000). The total number of balls doesn't exceed 1000. Output A single integer, the number of ways that Kyoya can draw the balls from the bag as described in the statement, modulo 1 000 000 007. Examples Input 3 2 2 1 Output 3 Input 4 1 2 3 4 Output 1680 Note In the first sample, we have 2 balls of color 1, 2 balls of color 2, and 1 ball of color 3. The three ways for Kyoya are: 1 2 1 2 3 1 1 2 2 3 2 1 1 2 3 Tags: combinatorics, dp, math Correct Solution: ``` # coding: utf-8 # In[6]: matrix = [[0 for x in range(1001)] for y in range(1001)] mod = 1000000007 def pascal(): matrix[0][0]=1; for i in range(1001): for j in range(1001): if j==0 or j==i: matrix[i][j]=1 else: matrix[i][j] = (matrix[i-1][j-1]+matrix[i-1][j])%mod a = int(input()) b = [] for i in range(a): b.append(int(input())) pascal() r = 1 s = b[0] for i in range(1,a): r = (r*matrix[s + b[i]-1][b[i]-1])%mod s += b[i] print(r) ```
90,522
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Kyoya Ootori has a bag with n colored balls that are colored with k different colors. The colors are labeled from 1 to k. Balls of the same color are indistinguishable. He draws balls from the bag one by one until the bag is empty. He noticed that he drew the last ball of color i before drawing the last ball of color i + 1 for all i from 1 to k - 1. Now he wonders how many different ways this can happen. Input The first line of input will have one integer k (1 ≤ k ≤ 1000) the number of colors. Then, k lines will follow. The i-th line will contain ci, the number of balls of the i-th color (1 ≤ ci ≤ 1000). The total number of balls doesn't exceed 1000. Output A single integer, the number of ways that Kyoya can draw the balls from the bag as described in the statement, modulo 1 000 000 007. Examples Input 3 2 2 1 Output 3 Input 4 1 2 3 4 Output 1680 Note In the first sample, we have 2 balls of color 1, 2 balls of color 2, and 1 ball of color 3. The three ways for Kyoya are: 1 2 1 2 3 1 1 2 2 3 2 1 1 2 3 Submitted Solution: ``` pt = [] for i in range(1000): pt.append([0] * (i + 1)) pt[i][0] = pt[i][i] = 1 for j in range(1, i): pt[i][j] = pt[i - 1][j - 1] + pt[i - 1][j] k, s, v = int(input()), int(input()), 1 for i in range(1, k): c = int(input()) v = v * pt[s + c - 1][c - 1] % 1000000007 s += c print(v) ``` Yes
90,523
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Kyoya Ootori has a bag with n colored balls that are colored with k different colors. The colors are labeled from 1 to k. Balls of the same color are indistinguishable. He draws balls from the bag one by one until the bag is empty. He noticed that he drew the last ball of color i before drawing the last ball of color i + 1 for all i from 1 to k - 1. Now he wonders how many different ways this can happen. Input The first line of input will have one integer k (1 ≤ k ≤ 1000) the number of colors. Then, k lines will follow. The i-th line will contain ci, the number of balls of the i-th color (1 ≤ ci ≤ 1000). The total number of balls doesn't exceed 1000. Output A single integer, the number of ways that Kyoya can draw the balls from the bag as described in the statement, modulo 1 000 000 007. Examples Input 3 2 2 1 Output 3 Input 4 1 2 3 4 Output 1680 Note In the first sample, we have 2 balls of color 1, 2 balls of color 2, and 1 ball of color 3. The three ways for Kyoya are: 1 2 1 2 3 1 1 2 2 3 2 1 1 2 3 Submitted Solution: ``` from sys import stdin input=lambda : stdin.readline().strip() from math import ceil,sqrt,factorial,gcd from collections import deque from bisect import bisect_right k=int(input()) ans=1 total=0 MOD=1000000007 for i in range(k): z=int(input()) ans=(ans*factorial(total+z-1)//factorial(total)//factorial(z-1))%MOD total+=z print(ans) ``` Yes
90,524
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Kyoya Ootori has a bag with n colored balls that are colored with k different colors. The colors are labeled from 1 to k. Balls of the same color are indistinguishable. He draws balls from the bag one by one until the bag is empty. He noticed that he drew the last ball of color i before drawing the last ball of color i + 1 for all i from 1 to k - 1. Now he wonders how many different ways this can happen. Input The first line of input will have one integer k (1 ≤ k ≤ 1000) the number of colors. Then, k lines will follow. The i-th line will contain ci, the number of balls of the i-th color (1 ≤ ci ≤ 1000). The total number of balls doesn't exceed 1000. Output A single integer, the number of ways that Kyoya can draw the balls from the bag as described in the statement, modulo 1 000 000 007. Examples Input 3 2 2 1 Output 3 Input 4 1 2 3 4 Output 1680 Note In the first sample, we have 2 balls of color 1, 2 balls of color 2, and 1 ball of color 3. The three ways for Kyoya are: 1 2 1 2 3 1 1 2 2 3 2 1 1 2 3 Submitted Solution: ``` from math import * from collections import deque from copy import deepcopy import sys def inp(): return sys.stdin.readline().rstrip("\r\n") #for fast input def multi(): return map(int,input().split()) def strmulti(): return map(str, inp().split()) def lis(): return list(map(int, inp().split())) def lcm(a,b): return (a*b)//gcd(a,b) def ncr(n,r): return factorial(n) // (factorial(r) * factorial(max(n - r, 1))) def stringlis(): return list(map(str, inp().split())) def out(var): sys.stdout.write(str(var)) #for fast output, always take string def printlist(a) : print(' '.join(str(a[i]) for i in range(len(a)))) def isPrime(n) : if (n <= 1) : return False if (n <= 3) : return True if (n % 2 == 0 or n % 3 == 0) : return False i = 5 while(i * i <= n) : if (n % i == 0 or n % (i + 2) == 0) : return False i = i + 6 return True #copied functions end #start coding k=int(input()) ans=1 sum=0 for i in range(k): num=int(input()) sum+=num ans*=(ncr(sum-1,num-1)) # print(ans) print(ans%1000000007) ``` Yes
90,525
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Kyoya Ootori has a bag with n colored balls that are colored with k different colors. The colors are labeled from 1 to k. Balls of the same color are indistinguishable. He draws balls from the bag one by one until the bag is empty. He noticed that he drew the last ball of color i before drawing the last ball of color i + 1 for all i from 1 to k - 1. Now he wonders how many different ways this can happen. Input The first line of input will have one integer k (1 ≤ k ≤ 1000) the number of colors. Then, k lines will follow. The i-th line will contain ci, the number of balls of the i-th color (1 ≤ ci ≤ 1000). The total number of balls doesn't exceed 1000. Output A single integer, the number of ways that Kyoya can draw the balls from the bag as described in the statement, modulo 1 000 000 007. Examples Input 3 2 2 1 Output 3 Input 4 1 2 3 4 Output 1680 Note In the first sample, we have 2 balls of color 1, 2 balls of color 2, and 1 ball of color 3. The three ways for Kyoya are: 1 2 1 2 3 1 1 2 2 3 2 1 1 2 3 Submitted Solution: ``` def binomialCoefficient(n, k): if(k > n - k): k = n - k res = 1 for i in range(k): res = res * (n - i) res = res // (i + 1) return res k=int(input()) sum=0 ans=1 m=1000000007 for i in range(k): a=int(input()) ans=(ans%m)*(binomialCoefficient(sum+a-1,a-1))%m sum+=a print(ans) ``` Yes
90,526
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Kyoya Ootori has a bag with n colored balls that are colored with k different colors. The colors are labeled from 1 to k. Balls of the same color are indistinguishable. He draws balls from the bag one by one until the bag is empty. He noticed that he drew the last ball of color i before drawing the last ball of color i + 1 for all i from 1 to k - 1. Now he wonders how many different ways this can happen. Input The first line of input will have one integer k (1 ≤ k ≤ 1000) the number of colors. Then, k lines will follow. The i-th line will contain ci, the number of balls of the i-th color (1 ≤ ci ≤ 1000). The total number of balls doesn't exceed 1000. Output A single integer, the number of ways that Kyoya can draw the balls from the bag as described in the statement, modulo 1 000 000 007. Examples Input 3 2 2 1 Output 3 Input 4 1 2 3 4 Output 1680 Note In the first sample, we have 2 balls of color 1, 2 balls of color 2, and 1 ball of color 3. The three ways for Kyoya are: 1 2 1 2 3 1 1 2 2 3 2 1 1 2 3 Submitted Solution: ``` k=int(input()) l=[int(input()) for i in range(k)] s=0 ans=[0]*k ans[0]=1 MOD=10**9+7 fact=[0]*(10**6+5) fact[0]=1 for i in range(1,10**6+5): fact[i]=(fact[i-1]*i)%MOD #print(fact[0:10]) def c(n,k): if k>=n: return 1 if k==0 or k==n: return 1 return fact[n]//(fact[k]*fact[n-k])%MOD ans=1 sm=l[0] for i in range(1,k): curr=l[i] #ans[i]=ans[i-1]+ ans=ans*(c(sm+curr-1,curr-1)) ans%=MOD sm+=l[i] print(ans) ``` No
90,527
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Kyoya Ootori has a bag with n colored balls that are colored with k different colors. The colors are labeled from 1 to k. Balls of the same color are indistinguishable. He draws balls from the bag one by one until the bag is empty. He noticed that he drew the last ball of color i before drawing the last ball of color i + 1 for all i from 1 to k - 1. Now he wonders how many different ways this can happen. Input The first line of input will have one integer k (1 ≤ k ≤ 1000) the number of colors. Then, k lines will follow. The i-th line will contain ci, the number of balls of the i-th color (1 ≤ ci ≤ 1000). The total number of balls doesn't exceed 1000. Output A single integer, the number of ways that Kyoya can draw the balls from the bag as described in the statement, modulo 1 000 000 007. Examples Input 3 2 2 1 Output 3 Input 4 1 2 3 4 Output 1680 Note In the first sample, we have 2 balls of color 1, 2 balls of color 2, and 1 ball of color 3. The three ways for Kyoya are: 1 2 1 2 3 1 1 2 2 3 2 1 1 2 3 Submitted Solution: ``` from functools import reduce from operator import mul mod = 10 ** 9 + 7 k = int(input()) cs = [int(input()) for _ in range(k)] cumcs = cs[:] for i in range(1, len(cs)): cumcs[i] += cumcs[i - 1] def C(n, k): num = reduce(mul, range(n, n - k, -1), 1) denom = reduce(mul, range(k, 0, -1), 1) return (num // denom) % mod res = 1 for cum, c in zip(cumcs, cs): res *= C(cum - 1, c - 1) print(res) ``` No
90,528
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Kyoya Ootori has a bag with n colored balls that are colored with k different colors. The colors are labeled from 1 to k. Balls of the same color are indistinguishable. He draws balls from the bag one by one until the bag is empty. He noticed that he drew the last ball of color i before drawing the last ball of color i + 1 for all i from 1 to k - 1. Now he wonders how many different ways this can happen. Input The first line of input will have one integer k (1 ≤ k ≤ 1000) the number of colors. Then, k lines will follow. The i-th line will contain ci, the number of balls of the i-th color (1 ≤ ci ≤ 1000). The total number of balls doesn't exceed 1000. Output A single integer, the number of ways that Kyoya can draw the balls from the bag as described in the statement, modulo 1 000 000 007. Examples Input 3 2 2 1 Output 3 Input 4 1 2 3 4 Output 1680 Note In the first sample, we have 2 balls of color 1, 2 balls of color 2, and 1 ball of color 3. The three ways for Kyoya are: 1 2 1 2 3 1 1 2 2 3 2 1 1 2 3 Submitted Solution: ``` from math import * from collections import deque from copy import deepcopy import sys def inp(): return sys.stdin.readline().rstrip("\r\n") #for fast input def multi(): return map(int,input().split()) def strmulti(): return map(str, inp().split()) def lis(): return list(map(int, inp().split())) def lcm(a,b): return (a*b)//gcd(a,b) def ncr(n,r): return factorial(n) // (factorial(r) * factorial(max(n - r, 1))) def stringlis(): return list(map(str, inp().split())) def out(var): sys.stdout.write(str(var)) #for fast output, always take string def printlist(a) : print(' '.join(str(a[i]) for i in range(len(a)))) def isPrime(n) : if (n <= 1) : return False if (n <= 3) : return True if (n % 2 == 0 or n % 3 == 0) : return False i = 5 while(i * i <= n) : if (n % i == 0 or n % (i + 2) == 0) : return False i = i + 6 return True #copied functions end #start coding k=int(input()) ans=1 sum=0 for i in range(k): num=int(input()) sum+=num ans*=(ncr(sum-1,num-1)) # print(ans) print(ans) ``` No
90,529
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Kyoya Ootori has a bag with n colored balls that are colored with k different colors. The colors are labeled from 1 to k. Balls of the same color are indistinguishable. He draws balls from the bag one by one until the bag is empty. He noticed that he drew the last ball of color i before drawing the last ball of color i + 1 for all i from 1 to k - 1. Now he wonders how many different ways this can happen. Input The first line of input will have one integer k (1 ≤ k ≤ 1000) the number of colors. Then, k lines will follow. The i-th line will contain ci, the number of balls of the i-th color (1 ≤ ci ≤ 1000). The total number of balls doesn't exceed 1000. Output A single integer, the number of ways that Kyoya can draw the balls from the bag as described in the statement, modulo 1 000 000 007. Examples Input 3 2 2 1 Output 3 Input 4 1 2 3 4 Output 1680 Note In the first sample, we have 2 balls of color 1, 2 balls of color 2, and 1 ball of color 3. The three ways for Kyoya are: 1 2 1 2 3 1 1 2 2 3 2 1 1 2 3 Submitted Solution: ``` from sys import stdin,stdout from collections import defaultdict import math #stdin = open('input.txt','r') I = stdin.readline P = stdout.write k = int(I()) tot = 0 ans = 1 for i in range(k): now = int(I()) ans*=math.factorial(tot+now-1)//math.factorial(tot)//math.factorial(now-1) tot+=now print(ans) ``` No
90,530
Provide tags and a correct Python 3 solution for this coding contest problem. You are given a string S of length n with each character being one of the first m lowercase English letters. Calculate how many different strings T of length n composed from the first m lowercase English letters exist such that the length of LCS (longest common subsequence) between S and T is n - 1. Recall that LCS of two strings S and T is the longest string C such that C both in S and T as a subsequence. Input The first line contains two numbers n and m denoting the length of string S and number of first English lowercase characters forming the character set for strings (1 ≤ n ≤ 100 000, 2 ≤ m ≤ 26). The second line contains string S. Output Print the only line containing the answer. Examples Input 3 3 aaa Output 6 Input 3 3 aab Output 11 Input 1 2 a Output 1 Input 10 9 abacadefgh Output 789 Note For the first sample, the 6 possible strings T are: aab, aac, aba, aca, baa, caa. For the second sample, the 11 possible strings T are: aaa, aac, aba, abb, abc, aca, acb, baa, bab, caa, cab. For the third sample, the only possible string T is b. Tags: dp, greedy Correct Solution: ``` def main(): n, m = map(int, input().split()) s = input() k = sum(s[i] != s[i - 1] for i in range(1, n)) + 1 x = i = 0 while i < n - 1: if s[i] != s[i + 1]: j = i while i + 2 < n and s[i] == s[i + 2]: i += 1 j = (i - j) + 2 x += j * (j - 1) // 2 i += 1 ans = k * (m * n - n) - x print(ans) main() ```
90,531
Provide tags and a correct Python 3 solution for this coding contest problem. You are given a rooted tree with root in vertex 1. Each vertex is coloured in some colour. Let's call colour c dominating in the subtree of vertex v if there are no other colours that appear in the subtree of vertex v more times than colour c. So it's possible that two or more colours will be dominating in the subtree of some vertex. The subtree of vertex v is the vertex v and all other vertices that contains vertex v in each path to the root. For each vertex v find the sum of all dominating colours in the subtree of vertex v. Input The first line contains integer n (1 ≤ n ≤ 105) — the number of vertices in the tree. The second line contains n integers ci (1 ≤ ci ≤ n), ci — the colour of the i-th vertex. Each of the next n - 1 lines contains two integers xj, yj (1 ≤ xj, yj ≤ n) — the edge of the tree. The first vertex is the root of the tree. Output Print n integers — the sums of dominating colours for each vertex. Examples Input 4 1 2 3 4 1 2 2 3 2 4 Output 10 9 3 4 Input 15 1 2 3 1 2 3 3 1 1 3 2 2 1 2 3 1 2 1 3 1 4 1 14 1 15 2 5 2 6 2 7 3 8 3 9 3 10 4 11 4 12 4 13 Output 6 5 4 3 2 3 3 1 1 3 2 2 1 2 3 Tags: data structures, dfs and similar, dsu, trees Correct Solution: ``` import sys input = sys.stdin.buffer.readline class SegmentTree: def __init__(self, n, op, e): self.n = n self.op = op self.e = e self.size = 2 ** ((n - 1).bit_length()) self.node = [self.e] * (2 * self.size) def __getitem__(self, i): return self.node[i + self.size] def __setitem__(self, i, val): i += self.size self.node[i] = val while i > 1: i >>= 1 self.node[i] = self.op(self.node[i << 1], self.node[(i << 1) + 1]) def build(self, array): for i, val in enumerate(array, self.size): self.node[i] = val for i in range(self.size - 1, 0, -1): self.node[i] = self.op(self.node[i << 1], self.node[(i << 1) + 1]) def all_fold(self): return self.node[1] def fold(self, l, r): l, r = l + self.size, r + self.size vl, vr = self.e, self.e while l < r: if l & 1: vl = self.op(vl, self.node[l]) l += 1 if r & 1: r -= 1 vr = self.op(self.node[r], vr) l, r = l >> 1, r >> 1 return self.op(vl, vr) def topological_sorted(tree, root=None): n = len(tree) par = [-1] * n tp_order = [] for v in range(n): if par[v] != -1 or (root is not None and v != root): continue stack = [v] while stack: v = stack.pop() tp_order.append(v) for nxt_v in tree[v]: if nxt_v == par[v]: continue par[nxt_v] = v stack.append(nxt_v) return tp_order, par def dsu_on_tree(tree, root): n = len(tree) tp_order, par = topological_sorted(tree, root) # 有向木の構築 di_tree = [[] for i in range(n)] for v in range(n): for nxt_v in tree[v]: if nxt_v == par[v]: continue di_tree[v].append(nxt_v) # 部分木サイズの計算 sub_size = [1] * n for v in tp_order[::-1]: for nxt_v in di_tree[v]: sub_size[v] += sub_size[nxt_v] # 有向木のDFS帰りがけ順の構築 di_tree = [sorted(tr, key=lambda v: sub_size[v]) for tr in di_tree] keeps = [0] * n for v in range(n): di_tree[v] = di_tree[v][:-1][::-1] + di_tree[v][-1:] for chi_v in di_tree[v][:-1]: keeps[chi_v] = 1 tp_order, _ = topological_sorted(di_tree, root) # counts = {} def add(sub_root, val): stack = [sub_root] while stack: v = stack.pop() vals = st[colors[v]] st[colors[v]] = (vals[0] + val, vals[1]) # counts[colors[v]] = counts.get(colors[v], 0) + val for chi_v in di_tree[v]: stack.append(chi_v) for v in tp_order[::-1]: for chi_v in di_tree[v]: if keeps[chi_v] == 1: add(chi_v, 1) vals = st[colors[v]] st[colors[v]] = (vals[0] + 1, vals[1]) # counts[colors[v]] = counts.get(colors[v], 0) + 1 ans[v] = st.all_fold()[1] if keeps[v] == 1: add(v, -1) n = int(input()) colors = list(map(int, input().split())) edges = [list(map(int, input().split())) for i in range(n - 1)] tree = [[] for i in range(n)] for u, v in edges: u -= 1 v -= 1 tree[u].append(v) tree[v].append(u) def op(x, y): # x = (max, sum_val) if x[0] == y[0]: return x[0], x[1] + y[1] elif x[0] > y[0]: return x elif x[0] < y[0]: return y e = (0, 0) st = SegmentTree(10 ** 5 + 10, op, e) st.build([(0, i) for i in range(10 ** 5 + 10)]) ans = [0] * n dsu_on_tree(tree, 0) print(*ans) ```
90,532
Provide tags and a correct Python 3 solution for this coding contest problem. You are given a rooted tree with root in vertex 1. Each vertex is coloured in some colour. Let's call colour c dominating in the subtree of vertex v if there are no other colours that appear in the subtree of vertex v more times than colour c. So it's possible that two or more colours will be dominating in the subtree of some vertex. The subtree of vertex v is the vertex v and all other vertices that contains vertex v in each path to the root. For each vertex v find the sum of all dominating colours in the subtree of vertex v. Input The first line contains integer n (1 ≤ n ≤ 105) — the number of vertices in the tree. The second line contains n integers ci (1 ≤ ci ≤ n), ci — the colour of the i-th vertex. Each of the next n - 1 lines contains two integers xj, yj (1 ≤ xj, yj ≤ n) — the edge of the tree. The first vertex is the root of the tree. Output Print n integers — the sums of dominating colours for each vertex. Examples Input 4 1 2 3 4 1 2 2 3 2 4 Output 10 9 3 4 Input 15 1 2 3 1 2 3 3 1 1 3 2 2 1 2 3 1 2 1 3 1 4 1 14 1 15 2 5 2 6 2 7 3 8 3 9 3 10 4 11 4 12 4 13 Output 6 5 4 3 2 3 3 1 1 3 2 2 1 2 3 Tags: data structures, dfs and similar, dsu, trees Correct Solution: ``` # dsu on tree # logistics: if the problem asked to compute some value of a subtree # naive method would be for each node, compute the query value which would be O(n^2) because of doing dfs for each node # we want to reuse some information of subtree so that we do not need to recompute it # we can use concept of heavy-light decomposition which we divide the value into light nodes and heavy node # complexity proof: from collections import defaultdict as df from types import GeneratorType def bootstrap(f, stack=[]): def wrappedfunc(*args, **kwargs): if stack: return f(*args, **kwargs) else: to = f(*args, **kwargs) while True: if type(to) is GeneratorType: stack.append(to) to = next(to) else: stack.pop() if not stack: break to = stack[-1].send(to) return to return wrappedfunc timer = 0 @bootstrap def dfs(v, p): global timer tin[v] = timer ver[timer] = v timer += 1 for child in tree[v]: if child != p: yield dfs(child, v) size[v] += size[child] size[v] += 1 tout[v] = timer timer += 1 yield 0 def operation(mx, v, x): ans[cnt[color[v]]] -= color[v] cnt[color[v]] += x ans[cnt[color[v]]] += color[v] mx = max(mx, cnt[color[v]]) return mx @bootstrap def dfs1(v, pa, keep): mx = 0;mx_child = -1; big_child = -1 for child in tree[v]: if child != pa and size[child] > mx_child: mx_child = size[child] big_child = child for child in tree[v]: if child != pa and child != big_child: yield dfs1(child, v, 0) if big_child != -1: temp = yield dfs1(big_child, v, 1) mx = max(temp, mx) for child in tree[v]: if child != pa and child != big_child: for p in range(tin[child], tout[child]): # add operation #cnt[dist[ver[p]]] += 1 mx = operation(mx, ver[p], 1) #add itself mx = operation(mx,v,1) #print(v,mx) res[v - 1] = ans[mx] #put answer above if not keep: for p in range(tin[v], tout[v]): # cancel operation #cnt[dist[ver[p]]] -= 1 mx = operation(mx, ver[p], -1) yield mx if __name__ == '__main__': n = int(input().strip()) #arr = list(map(int, input().split())) color = [0] + list(map(int, input().split())) tree = df(list) for i in range(1,n): u,v = map(int, input().split()) tree[u].append(v) tree[v].append(u) #tree[arr[i - 1]].append(i + 1) #maxn = 100000 cnt = [0 for i in range(n + 1)] size = [0 for i in range(n + 1)] ver = [0 for i in range((n + 1) << 1)] tin = [0 for i in range(n + 1)] tout = [0 for i in range(n + 1)] ans = [0 for i in range(n + 1)] res = [0 for i in range(n)] #dist = [0 for i in range(n + 1)] # query = int(input().strip()) # queries = df(list) # res = df(int) # for i in range(query): # u, d = map(int, input().split()) # queries[u].append((d,i)) dfs(1, 1) dfs1(1,1,1) #res[0] = ans print(' '.join(str(i) for i in res)) ```
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Provide tags and a correct Python 3 solution for this coding contest problem. You are given a rooted tree with root in vertex 1. Each vertex is coloured in some colour. Let's call colour c dominating in the subtree of vertex v if there are no other colours that appear in the subtree of vertex v more times than colour c. So it's possible that two or more colours will be dominating in the subtree of some vertex. The subtree of vertex v is the vertex v and all other vertices that contains vertex v in each path to the root. For each vertex v find the sum of all dominating colours in the subtree of vertex v. Input The first line contains integer n (1 ≤ n ≤ 105) — the number of vertices in the tree. The second line contains n integers ci (1 ≤ ci ≤ n), ci — the colour of the i-th vertex. Each of the next n - 1 lines contains two integers xj, yj (1 ≤ xj, yj ≤ n) — the edge of the tree. The first vertex is the root of the tree. Output Print n integers — the sums of dominating colours for each vertex. Examples Input 4 1 2 3 4 1 2 2 3 2 4 Output 10 9 3 4 Input 15 1 2 3 1 2 3 3 1 1 3 2 2 1 2 3 1 2 1 3 1 4 1 14 1 15 2 5 2 6 2 7 3 8 3 9 3 10 4 11 4 12 4 13 Output 6 5 4 3 2 3 3 1 1 3 2 2 1 2 3 Tags: data structures, dfs and similar, dsu, trees Correct Solution: ``` import sys input = sys.stdin.buffer.readline class SegmentTree: def __init__(self, n, op, e): self.n = n self.op = op self.e = e self.size = 2 ** ((n - 1).bit_length()) self.node = [self.e] * (2 * self.size) def __getitem__(self, i): return self.node[i + self.size] def __setitem__(self, i, val): i += self.size self.node[i] = val while i > 1: i >>= 1 self.node[i] = self.op(self.node[i << 1], self.node[(i << 1) + 1]) def build(self, array): for i, val in enumerate(array, self.size): self.node[i] = val for i in range(self.size - 1, 0, -1): self.node[i] = self.op(self.node[i << 1], self.node[(i << 1) + 1]) def all_fold(self): return self.node[1] def fold(self, l, r): l, r = l + self.size, r + self.size vl, vr = self.e, self.e while l < r: if l & 1: vl = self.op(vl, self.node[l]) l += 1 if r & 1: r -= 1 vr = self.op(self.node[r], vr) l, r = l >> 1, r >> 1 return self.op(vl, vr) def topological_sorted(tree, root=None): n = len(tree) par = [-1] * n tp_order = [] for v in range(n): if par[v] != -1 or (root is not None and v != root): continue stack = [v] while stack: v = stack.pop() tp_order.append(v) for nxt_v in tree[v]: if nxt_v == par[v]: continue par[nxt_v] = v stack.append(nxt_v) return tp_order, par def dsu_on_tree(tree, root): n = len(tree) tp_order, par = topological_sorted(tree, root) # 有向木の構築 di_tree = [[] for i in range(n)] for v in range(n): for nxt_v in tree[v]: if nxt_v == par[v]: continue di_tree[v].append(nxt_v) # 部分木サイズの計算 sub_size = [1] * n for v in tp_order[::-1]: for nxt_v in di_tree[v]: sub_size[v] += sub_size[nxt_v] # 有向木のDFS行きがけ順の構築 di_tree = [sorted(tr, key=lambda v: sub_size[v]) for tr in di_tree] keeps = [0] * n for v in range(n): di_tree[v] = di_tree[v][:-1][::-1] + di_tree[v][-1:] for chi_v in di_tree[v][:-1]: keeps[chi_v] = 1 tp_order, _ = topological_sorted(di_tree, root) # 加算もしくは減算の実行 # counts = {} def add(sub_root, val): stack = [sub_root] while stack: v = stack.pop() vals = st[colors[v]] st[colors[v]] = (vals[0] + val, vals[1]) # counts[colors[v]] = counts.get(colors[v], 0) + val for chi_v in di_tree[v]: stack.append(chi_v) # 有向木のDFS帰りがけ順で処理 for v in tp_order[::-1]: for chi_v in di_tree[v]: if keeps[chi_v] == 1: add(chi_v, 1) # ここでクエリを実行する vals = st[colors[v]] st[colors[v]] = (vals[0] + 1, vals[1]) # counts[colors[v]] = counts.get(colors[v], 0) + 1 ans[v] = st.all_fold()[1] if keeps[v] == 1: add(v, -1) n = int(input()) colors = list(map(int, input().split())) edges = [list(map(int, input().split())) for i in range(n - 1)] tree = [[] for i in range(n)] for u, v in edges: u -= 1 v -= 1 tree[u].append(v) tree[v].append(u) def op(x, y): # x = (max, sum_val) if x[0] == y[0]: return x[0], x[1] + y[1] elif x[0] > y[0]: return x elif x[0] < y[0]: return y e = (0, 0) st = SegmentTree(10 ** 5 + 10, op, e) st.build([(0, i) for i in range(10 ** 5 + 10)]) ans = [0] * n dsu_on_tree(tree, 0) print(*ans) ```
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Provide tags and a correct Python 3 solution for this coding contest problem. You are given a rooted tree with root in vertex 1. Each vertex is coloured in some colour. Let's call colour c dominating in the subtree of vertex v if there are no other colours that appear in the subtree of vertex v more times than colour c. So it's possible that two or more colours will be dominating in the subtree of some vertex. The subtree of vertex v is the vertex v and all other vertices that contains vertex v in each path to the root. For each vertex v find the sum of all dominating colours in the subtree of vertex v. Input The first line contains integer n (1 ≤ n ≤ 105) — the number of vertices in the tree. The second line contains n integers ci (1 ≤ ci ≤ n), ci — the colour of the i-th vertex. Each of the next n - 1 lines contains two integers xj, yj (1 ≤ xj, yj ≤ n) — the edge of the tree. The first vertex is the root of the tree. Output Print n integers — the sums of dominating colours for each vertex. Examples Input 4 1 2 3 4 1 2 2 3 2 4 Output 10 9 3 4 Input 15 1 2 3 1 2 3 3 1 1 3 2 2 1 2 3 1 2 1 3 1 4 1 14 1 15 2 5 2 6 2 7 3 8 3 9 3 10 4 11 4 12 4 13 Output 6 5 4 3 2 3 3 1 1 3 2 2 1 2 3 Tags: data structures, dfs and similar, dsu, trees Correct Solution: ``` import sys input = sys.stdin.buffer.readline class SegmentTree: def __init__(self, n, op, e): self.n = n self.op = op self.e = e self.size = 2 ** ((n - 1).bit_length()) self.node = [self.e] * (2 * self.size) def __getitem__(self, i): return self.node[i + self.size] def __setitem__(self, i, val): i += self.size self.node[i] = val while i > 1: i >>= 1 self.node[i] = self.op(self.node[i << 1], self.node[(i << 1) + 1]) def build(self, array): for i, val in enumerate(array, self.size): self.node[i] = val for i in range(self.size - 1, 0, -1): self.node[i] = self.op(self.node[i << 1], self.node[(i << 1) + 1]) def all_fold(self): return self.node[1] def fold(self, l, r): l, r = l + self.size, r + self.size vl, vr = self.e, self.e while l < r: if l & 1: vl = self.op(vl, self.node[l]) l += 1 if r & 1: r -= 1 vr = self.op(self.node[r], vr) l, r = l >> 1, r >> 1 return self.op(vl, vr) def topological_sorted(tree, root=None): n = len(tree) par = [-1] * n tp_order = [] for v in range(n): if par[v] != -1 or (root is not None and v != root): continue stack = [v] while stack: v = stack.pop() tp_order.append(v) for nxt_v in tree[v]: if nxt_v == par[v]: continue par[nxt_v] = v stack.append(nxt_v) return tp_order, par def dsu_on_tree(tree, root, add, sub, query): n = len(tree) tp_order, par = topological_sorted(tree, root) # 1.有向木の構築 di_tree = [[] for i in range(n)] for v in range(n): for nxt_v in tree[v]: if nxt_v == par[v]: continue di_tree[v].append(nxt_v) # 2.部分木サイズの計算 sub_size = [1] * n for v in tp_order[::-1]: for nxt_v in di_tree[v]: sub_size[v] += sub_size[nxt_v] # 3.有向木のDFS行きがけ順の構築 di_tree = [sorted(tr, key=lambda v: sub_size[v]) for tr in di_tree] keeps = [0] * n for v in range(n): di_tree[v] = di_tree[v][:-1][::-1] + di_tree[v][-1:] for chi_v in di_tree[v][-1:]: keeps[chi_v] = 1 tp_order, _ = topological_sorted(di_tree, root) # 部分木からの加算もしくは減算 def calc(sub_root, is_add): stack = [sub_root] while stack: v = stack.pop() add(v) if is_add else sub(v) for chi_v in di_tree[v]: stack.append(chi_v) # 4.有向木のDFS帰りがけ順で頂点vの部分木クエリを処理 for v in tp_order[::-1]: for chi_v in di_tree[v]: if keeps[chi_v] == 0: calc(chi_v, 1) add(v) # ここでクエリを実行する query(v) if keeps[v] == 0: calc(v, 0) n = int(input()) colors = list(map(int, input().split())) edges = [list(map(int, input().split())) for i in range(n - 1)] tree = [[] for i in range(n)] for u, v in edges: u -= 1 v -= 1 tree[u].append(v) tree[v].append(u) def op(x, y): # x = (max, sum_val) if x[0] == y[0]: return x[0], x[1] + y[1] elif x[0] > y[0]: return x elif x[0] < y[0]: return y e = (0, 0) st = SegmentTree(10 ** 5 + 10, op, e) st.build([(0, i) for i in range(10 ** 5 + 10)]) def add(v): max_, sum_ = st[colors[v]] st[colors[v]] = (max_ + 1, sum_) def sub(v): max_, sum_ = st[colors[v]] st[colors[v]] = (max_ - 1, sum_) ans = [0] * n def query(v): max_, sum_ = st.all_fold() ans[v] = sum_ dsu_on_tree(tree, 0, add, sub, query) print(*ans) ```
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Provide tags and a correct Python 3 solution for this coding contest problem. You are given a rooted tree with root in vertex 1. Each vertex is coloured in some colour. Let's call colour c dominating in the subtree of vertex v if there are no other colours that appear in the subtree of vertex v more times than colour c. So it's possible that two or more colours will be dominating in the subtree of some vertex. The subtree of vertex v is the vertex v and all other vertices that contains vertex v in each path to the root. For each vertex v find the sum of all dominating colours in the subtree of vertex v. Input The first line contains integer n (1 ≤ n ≤ 105) — the number of vertices in the tree. The second line contains n integers ci (1 ≤ ci ≤ n), ci — the colour of the i-th vertex. Each of the next n - 1 lines contains two integers xj, yj (1 ≤ xj, yj ≤ n) — the edge of the tree. The first vertex is the root of the tree. Output Print n integers — the sums of dominating colours for each vertex. Examples Input 4 1 2 3 4 1 2 2 3 2 4 Output 10 9 3 4 Input 15 1 2 3 1 2 3 3 1 1 3 2 2 1 2 3 1 2 1 3 1 4 1 14 1 15 2 5 2 6 2 7 3 8 3 9 3 10 4 11 4 12 4 13 Output 6 5 4 3 2 3 3 1 1 3 2 2 1 2 3 Tags: data structures, dfs and similar, dsu, trees Correct Solution: ``` from collections import defaultdict class SumDefaultdict(defaultdict): def __init__(self, *args, **kwargs) -> None: super().__init__(int, *args, **kwargs) self.mx = max(self.values()) self.mx_sum = sum(c for c, v in self.items() if v == self.mx) def sumadd(self, map): for bb, val in map.items(): if val > 0: self[bb] += val if self[bb] > self.mx: self.mx = self[bb] self.mx_sum = bb elif self[bb] == self.mx: self.mx_sum += bb def go(): n = int(input()) c = list(map(int, input().split())) edges = [[] for _ in range(n)] for _ in range(n - 1): a, b = map(lambda x: int(x) - 1, input().split()) edges[a].append(b) edges[b].append(a) depth = [0] + [None] * (n - 1) parent = [None] * n que = [0] index = 0 while index < len(que): curr = que[index] for b in edges[curr]: if depth[b] is None: depth[b] = depth[curr] + 1 parent[b] = curr que.append(b) index += 1 order = sorted(((depth[i], i) for i in range(n)), reverse=True) cols = [SumDefaultdict({c[i]: 1}) for i in range(n)] answer = [0] * n for d, i in order: children = sorted([cols[b] for b in edges[i] if depth[b] > d], key=len, reverse=True) if children: for j in range(1, len(children)): children[0].sumadd(children[j]) children[0].sumadd({c[i]: 1}) cols[i] = children[0] # max_val = max(cols[i].values()) answer[i] = cols[i].mx_sum print(' '.join(map(str, answer))) go() ```
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Provide tags and a correct Python 3 solution for this coding contest problem. You are given a rooted tree with root in vertex 1. Each vertex is coloured in some colour. Let's call colour c dominating in the subtree of vertex v if there are no other colours that appear in the subtree of vertex v more times than colour c. So it's possible that two or more colours will be dominating in the subtree of some vertex. The subtree of vertex v is the vertex v and all other vertices that contains vertex v in each path to the root. For each vertex v find the sum of all dominating colours in the subtree of vertex v. Input The first line contains integer n (1 ≤ n ≤ 105) — the number of vertices in the tree. The second line contains n integers ci (1 ≤ ci ≤ n), ci — the colour of the i-th vertex. Each of the next n - 1 lines contains two integers xj, yj (1 ≤ xj, yj ≤ n) — the edge of the tree. The first vertex is the root of the tree. Output Print n integers — the sums of dominating colours for each vertex. Examples Input 4 1 2 3 4 1 2 2 3 2 4 Output 10 9 3 4 Input 15 1 2 3 1 2 3 3 1 1 3 2 2 1 2 3 1 2 1 3 1 4 1 14 1 15 2 5 2 6 2 7 3 8 3 9 3 10 4 11 4 12 4 13 Output 6 5 4 3 2 3 3 1 1 3 2 2 1 2 3 Tags: data structures, dfs and similar, dsu, trees Correct Solution: ``` import sys from collections import Counter n = int(input()) color = list(map(int, input().split())) adj = [[] for _ in range(n)] for _ in range(n-1): u, v = map(int, sys.stdin.readline().split()) u -= 1 v -= 1 adj[u].append(v) adj[v].append(u) count = [Counter() for _ in range(n)] max_cnt = [0]*n dp = [0]*n stack = [0] par = [-1]*n order = [] while stack: v = stack.pop() order.append(v) for d in adj[v]: if d != par[v]: stack.append(d) par[d] = v for v in reversed(order): child = [i for i in adj[v] if i != par[v]] child.sort(key=lambda v: -len(count[v])) if child: dp[v] = dp[child[0]] max_cnt[v] = max_cnt[child[0]] count[v] = count[child[0]] for d in child[1:]: for k, val in count[d].items(): count[v][k] += val if count[v][k] > max_cnt[v]: dp[v] = k max_cnt[v] = count[v][k] elif count[v][k] == max_cnt[v]: dp[v] += k count[v][color[v]] += 1 if count[v][color[v]] > max_cnt[v]: dp[v] = color[v] max_cnt[v] = count[v][color[v]] elif count[v][color[v]] == max_cnt[v]: dp[v] += color[v] if par[v] != -1: stack.append(par[v]) print(*dp) ```
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Provide tags and a correct Python 3 solution for this coding contest problem. You are given a rooted tree with root in vertex 1. Each vertex is coloured in some colour. Let's call colour c dominating in the subtree of vertex v if there are no other colours that appear in the subtree of vertex v more times than colour c. So it's possible that two or more colours will be dominating in the subtree of some vertex. The subtree of vertex v is the vertex v and all other vertices that contains vertex v in each path to the root. For each vertex v find the sum of all dominating colours in the subtree of vertex v. Input The first line contains integer n (1 ≤ n ≤ 105) — the number of vertices in the tree. The second line contains n integers ci (1 ≤ ci ≤ n), ci — the colour of the i-th vertex. Each of the next n - 1 lines contains two integers xj, yj (1 ≤ xj, yj ≤ n) — the edge of the tree. The first vertex is the root of the tree. Output Print n integers — the sums of dominating colours for each vertex. Examples Input 4 1 2 3 4 1 2 2 3 2 4 Output 10 9 3 4 Input 15 1 2 3 1 2 3 3 1 1 3 2 2 1 2 3 1 2 1 3 1 4 1 14 1 15 2 5 2 6 2 7 3 8 3 9 3 10 4 11 4 12 4 13 Output 6 5 4 3 2 3 3 1 1 3 2 2 1 2 3 Tags: data structures, dfs and similar, dsu, trees Correct Solution: ``` def main(): import sys from collections import deque input = sys.stdin.readline N = int(input()) color = list(map(int, input().split())) color.insert(0, 0) adj = [[] for _ in range(N+1)] for _ in range(N-1): a, b = map(int, input().split()) adj[a].append(b) adj[b].append(a) que = deque() que.append(1) seen = [-1] * (N+1) seen[1] = 0 par = [0] * (N+1) child = [[] for _ in range(N+1)] seq = [] while que: v = que.popleft() seq.append(v) for u in adj[v]: if seen[u] == -1: seen[u] = seen[v] + 1 par[u] = v child[v].append(u) que.append(u) seq.reverse() cnt = [{color[i]: 1} for i in range(N+1)] cnt_size = [1] * (N+1) dom_num = [1] * (N+1) ans = [color[i] for i in range(N+1)] for v in seq: big = cnt[v] size_big = cnt_size[v] for u in child[v]: small = cnt[u] size_small = cnt_size[u] if size_big < size_small: small, big = big, small dom_num[v] = dom_num[u] ans[v] = ans[u] size_big += size_small for c in small: if c not in big: big[c] = small[c] else: big[c] += small[c] cnt_size[v] += small[c] if big[c] > dom_num[v]: dom_num[v] = big[c] ans[v] = c elif big[c] == dom_num[v]: ans[v] += c cnt_size[v] = size_big cnt[v] = big print(*ans[1:]) #print(child) #print(cnt) #print(cnt_size) if __name__ == '__main__': main() ```
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Provide tags and a correct Python 3 solution for this coding contest problem. You are given a rooted tree with root in vertex 1. Each vertex is coloured in some colour. Let's call colour c dominating in the subtree of vertex v if there are no other colours that appear in the subtree of vertex v more times than colour c. So it's possible that two or more colours will be dominating in the subtree of some vertex. The subtree of vertex v is the vertex v and all other vertices that contains vertex v in each path to the root. For each vertex v find the sum of all dominating colours in the subtree of vertex v. Input The first line contains integer n (1 ≤ n ≤ 105) — the number of vertices in the tree. The second line contains n integers ci (1 ≤ ci ≤ n), ci — the colour of the i-th vertex. Each of the next n - 1 lines contains two integers xj, yj (1 ≤ xj, yj ≤ n) — the edge of the tree. The first vertex is the root of the tree. Output Print n integers — the sums of dominating colours for each vertex. Examples Input 4 1 2 3 4 1 2 2 3 2 4 Output 10 9 3 4 Input 15 1 2 3 1 2 3 3 1 1 3 2 2 1 2 3 1 2 1 3 1 4 1 14 1 15 2 5 2 6 2 7 3 8 3 9 3 10 4 11 4 12 4 13 Output 6 5 4 3 2 3 3 1 1 3 2 2 1 2 3 Tags: data structures, dfs and similar, dsu, trees Correct Solution: ``` import os import sys from io import BytesIO, IOBase _str = str BUFSIZE = 8192 def str(x=b''): return x if type(x) is bytes else _str(x).encode() class FastIO(IOBase): newlines = 0 def __init__(self, file): self._fd = file.fileno() self.buffer = BytesIO() self.writable = 'x' in file.mode or 'r' not in file.mode self.write = self.buffer.write if self.writable else None def read(self): while True: b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE)) if not b: break ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines = 0 return self.buffer.read() def readline(self): while self.newlines == 0: b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE)) self.newlines = b.count(b'\n') + (not b) ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines -= 1 return self.buffer.readline() def flush(self): if self.writable: os.write(self._fd, self.buffer.getvalue()) self.buffer.truncate(0), self.buffer.seek(0) class IOWrapper(IOBase): def __init__(self, file): self.buffer = FastIO(file) self.flush = self.buffer.flush self.writable = self.buffer.writable self.write = lambda s: self.buffer.write(s.encode('ascii')) self.read = lambda: self.buffer.read().decode('ascii') self.readline = lambda: self.buffer.readline().decode('ascii') def inp(): return sys.stdin.readline().rstrip() def mpint(): return map(int, inp().split(' ')) def itg(): return int(inp()) # ############################## import # from ACgenerator.Y_Testing import get_code def tree_bfs(tree, flat=True, start=0) -> list: stack = [start] result = [] while stack: new_stack = [] if flat: result.extend(stack) else: result.append(stack) for node in stack: new_stack.extend(tree[node]) stack = new_stack return result def to_tree(graph, root=0): """ graph: [{child, ...}, ...] (undirected) :return directed graph that parent -> children """ stack = [[root]] while stack: if not stack[-1]: del stack[-1] continue parent = stack[-1].pop() for child in graph[parent]: graph[child].discard(parent) stack.append(list(graph[parent])) def tree_postorder(tree, flat=True, root=0): """ children -> parent """ return tree_bfs(tree, flat, root)[::-1] # ############################## main from collections import defaultdict class Counter: def __init__(self, c): self.ans = c self.c_t = defaultdict(lambda: 0) self.mx = self.c_t[c] = 1 self.t_c = defaultdict(set) self.t_c[1] = {c} def merge(self, other): for c, t in other.c_t.items(): self.add(c, t) def add(self, c, t): old_t = self.c_t[c] self.c_t[c] = new_t = old_t + t self.t_c[old_t].discard(c) self.t_c[new_t].add(c) if new_t == self.mx: self.ans += c elif new_t > self.mx: self.mx = new_t self.ans = c def __len__(self): return len(self.c_t) def __repr__(self): return _str(self.ans) def solve(): n = itg() ans = list(map(Counter, mpint())) tree = [set() for _ in range(n)] for _ in range(n - 1): a, b = mpint() a -= 1 b -= 1 tree[a].add(b) tree[b].add(a) to_tree(tree) for parent in tree_postorder(tree): for child in tree[parent]: child_ans = ans[child].ans if len(ans[parent]) < len(ans[child]): ans[parent], ans[child] = ans[child], ans[parent] ans[parent].merge(ans[child]) ans[child] = child_ans return ans def main(): # solve() print(*solve()) # for _ in range(itg()): # print(solve()) # print("YES" if solve() else "NO") # print("yes" if solve() else "no") DEBUG = 0 URL = 'https://codeforces.com/contest/600/problem/E' if __name__ == '__main__': if DEBUG == 1: import requests # ImportError: cannot import name 'md5' from 'sys' (unknown location) from ACgenerator.Y_Test_Case_Runner import TestCaseRunner runner = TestCaseRunner(main, URL) inp = runner.input_stream print = runner.output_stream runner.checking() elif DEBUG == 2: main() else: sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout) main() # Please check! ```
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given a rooted tree with root in vertex 1. Each vertex is coloured in some colour. Let's call colour c dominating in the subtree of vertex v if there are no other colours that appear in the subtree of vertex v more times than colour c. So it's possible that two or more colours will be dominating in the subtree of some vertex. The subtree of vertex v is the vertex v and all other vertices that contains vertex v in each path to the root. For each vertex v find the sum of all dominating colours in the subtree of vertex v. Input The first line contains integer n (1 ≤ n ≤ 105) — the number of vertices in the tree. The second line contains n integers ci (1 ≤ ci ≤ n), ci — the colour of the i-th vertex. Each of the next n - 1 lines contains two integers xj, yj (1 ≤ xj, yj ≤ n) — the edge of the tree. The first vertex is the root of the tree. Output Print n integers — the sums of dominating colours for each vertex. Examples Input 4 1 2 3 4 1 2 2 3 2 4 Output 10 9 3 4 Input 15 1 2 3 1 2 3 3 1 1 3 2 2 1 2 3 1 2 1 3 1 4 1 14 1 15 2 5 2 6 2 7 3 8 3 9 3 10 4 11 4 12 4 13 Output 6 5 4 3 2 3 3 1 1 3 2 2 1 2 3 Submitted Solution: ``` import sys import collections import random input = sys.stdin.readline d = collections.defaultdict(list) n = int(input()) col = [int(i) for i in input().split() ] for _ in range(n-1): a, b = map(int, input().split() ) d[a-1].append(b-1) d[b-1].append(a-1) def dfs(parent, node, que, cnt, m): makenew = False for i in d[node]: if i == parent: continue if makenew: q1, c1 = {}, {} dfs(node, i, q1, c1, [0]) for key in c1: #key = color if key in cnt: que[cnt[key]] -= key cnt[key] += c1[key] else: cnt[key] = c1[key] if cnt[key] not in que: que[cnt[key]] = 0 que[cnt[key]] += key if m[0] < cnt[key]: m[0] = cnt[key] continue dfs(node, i, que, cnt, m) makenew = True # leaves finish here: if len(que) == 0: que[1] = col[node] cnt[col[node]] = 1 m[0] = 1 return # nodes accumulating: if col[node] in cnt: que[cnt[col[node]]] -= col[node] cnt[col[node]] += 1 if cnt[col[node]] not in que: que[cnt[col[node]]] = 0 que[cnt[col[node]]] += col[node] if m[0] < cnt[col[node]]: m[0] = cnt[col[node]] else: cnt[col[node]] = 1 if 1 not in que: que[1] = 0 que[1] += col[node] col[node] = que[ m[0] ] return try: dfs(-1, 0, {}, {}, [0]) except RuntimeError as e: print(e) print( " ".join(list(map(str, col )))) ``` No
90,540
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given a rooted tree with root in vertex 1. Each vertex is coloured in some colour. Let's call colour c dominating in the subtree of vertex v if there are no other colours that appear in the subtree of vertex v more times than colour c. So it's possible that two or more colours will be dominating in the subtree of some vertex. The subtree of vertex v is the vertex v and all other vertices that contains vertex v in each path to the root. For each vertex v find the sum of all dominating colours in the subtree of vertex v. Input The first line contains integer n (1 ≤ n ≤ 105) — the number of vertices in the tree. The second line contains n integers ci (1 ≤ ci ≤ n), ci — the colour of the i-th vertex. Each of the next n - 1 lines contains two integers xj, yj (1 ≤ xj, yj ≤ n) — the edge of the tree. The first vertex is the root of the tree. Output Print n integers — the sums of dominating colours for each vertex. Examples Input 4 1 2 3 4 1 2 2 3 2 4 Output 10 9 3 4 Input 15 1 2 3 1 2 3 3 1 1 3 2 2 1 2 3 1 2 1 3 1 4 1 14 1 15 2 5 2 6 2 7 3 8 3 9 3 10 4 11 4 12 4 13 Output 6 5 4 3 2 3 3 1 1 3 2 2 1 2 3 Submitted Solution: ``` #600E cin = lambda:map(int,input().split()) n=int(input()) color=list(cin()) D=dict() for i in range(n-1): a,b=cin() if a not in D: D[a]={b} else: D[a].add(b) colorres=[0]*n def myadd(x, y): return list(map(lambda a, b: a + b, x, y)) def maxsum(l): maxc=max(l) res=0 for i in range(n+1): if l[i]==maxc: res+=i return(res) def myf(v): if v not in D: colorres[v-1]=color[v-1] l=[0]*(n+1) l[color[v-1]]=1 return l else: l=[0]*(n+1) l[color[v-1]]+=1 for vc in D[v]: l=myadd(l,myf(vc)) colorres[v-1]=maxsum(l) return(l) myf(1) print(' '.join(map(str, colorres ))) ``` No
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given a rooted tree with root in vertex 1. Each vertex is coloured in some colour. Let's call colour c dominating in the subtree of vertex v if there are no other colours that appear in the subtree of vertex v more times than colour c. So it's possible that two or more colours will be dominating in the subtree of some vertex. The subtree of vertex v is the vertex v and all other vertices that contains vertex v in each path to the root. For each vertex v find the sum of all dominating colours in the subtree of vertex v. Input The first line contains integer n (1 ≤ n ≤ 105) — the number of vertices in the tree. The second line contains n integers ci (1 ≤ ci ≤ n), ci — the colour of the i-th vertex. Each of the next n - 1 lines contains two integers xj, yj (1 ≤ xj, yj ≤ n) — the edge of the tree. The first vertex is the root of the tree. Output Print n integers — the sums of dominating colours for each vertex. Examples Input 4 1 2 3 4 1 2 2 3 2 4 Output 10 9 3 4 Input 15 1 2 3 1 2 3 3 1 1 3 2 2 1 2 3 1 2 1 3 1 4 1 14 1 15 2 5 2 6 2 7 3 8 3 9 3 10 4 11 4 12 4 13 Output 6 5 4 3 2 3 3 1 1 3 2 2 1 2 3 Submitted Solution: ``` import sys sys.setrecursionlimit(100000) input = sys.stdin.readline n = int(input()) vertexes = list(map(int, input().split())) tree_map = {} for i in range(n - 1): a, b = map(int, input().split()) if a in tree_map: tree_map[a].append(b) else: tree_map[a] = [b] freq = [-1 for i in range(n)] result = [-1 for i in range(n)] def sum_dict(a, b): for key in a: if key in b: b[key] += a[key] else: b[key] = a[key] return b def solve(node): if result[node - 1] != -1: return freq[node - 1] if node in tree_map: frequency = {vertexes[node - 1]: 1} for next_node in tree_map[node]: f = solve(next_node) frequency = sum_dict(f, frequency) n = max(frequency.values()) s = 0 for i in frequency: if frequency[i] == n: s += i result[node - 1] = s freq[node - 1] = frequency return frequency else: freq[node - 1] = {vertexes[node - 1]: 1} result[node - 1] = vertexes[node - 1] return freq[node - 1] solve(1) for i, n in enumerate(result): if n == -1: result[i] = vertexes[i] print(*result) ``` No
90,542
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given a rooted tree with root in vertex 1. Each vertex is coloured in some colour. Let's call colour c dominating in the subtree of vertex v if there are no other colours that appear in the subtree of vertex v more times than colour c. So it's possible that two or more colours will be dominating in the subtree of some vertex. The subtree of vertex v is the vertex v and all other vertices that contains vertex v in each path to the root. For each vertex v find the sum of all dominating colours in the subtree of vertex v. Input The first line contains integer n (1 ≤ n ≤ 105) — the number of vertices in the tree. The second line contains n integers ci (1 ≤ ci ≤ n), ci — the colour of the i-th vertex. Each of the next n - 1 lines contains two integers xj, yj (1 ≤ xj, yj ≤ n) — the edge of the tree. The first vertex is the root of the tree. Output Print n integers — the sums of dominating colours for each vertex. Examples Input 4 1 2 3 4 1 2 2 3 2 4 Output 10 9 3 4 Input 15 1 2 3 1 2 3 3 1 1 3 2 2 1 2 3 1 2 1 3 1 4 1 14 1 15 2 5 2 6 2 7 3 8 3 9 3 10 4 11 4 12 4 13 Output 6 5 4 3 2 3 3 1 1 3 2 2 1 2 3 Submitted Solution: ``` import sys sys.setrecursionlimit(100000) input = sys.stdin.readline n = int(input()) vertexes = list(map(int, input().split())) tree_map = {} for i in range(n - 1): a, b = map(int, input().split()) if a in tree_map: tree_map[a].append(b) else: tree_map[a] = [b] freq = [-1 for i in range(n)] result = [-1 for i in range(n)] def sum_dict(a, b): for key in a: if key in b: b[key] += a[key] else: b[key] = a[key] return b def solve(node): if result[node - 1] != -1: return freq[node - 1] if node in tree_map: frequency = {vertexes[node - 1]: 1} for next_node in tree_map[node]: f = solve(next_node) frequency = sum_dict(f, frequency) n = max(frequency.values()) s = 0 for i in frequency: if frequency[i] == n: s += i result[node - 1] = s freq[node - 1] = frequency return frequency else: freq[node - 1] = {vertexes[node - 1]: 1} result[node - 1] = vertexes[node - 1] return freq[node - 1] solve(1) if n == 4 or n == 15: print(*result) else: print(tree_map[1]) ``` No
90,543
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given array ai of length n. You may consecutively apply two operations to this array: * remove some subsegment (continuous subsequence) of length m < n and pay for it m·a coins; * change some elements of the array by at most 1, and pay b coins for each change. Please note that each of operations may be applied at most once (and may be not applied at all) so you can remove only one segment and each number may be changed (increased or decreased) by at most 1. Also note, that you are not allowed to delete the whole array. Your goal is to calculate the minimum number of coins that you need to spend in order to make the greatest common divisor of the elements of the resulting array be greater than 1. Input The first line of the input contains integers n, a and b (1 ≤ n ≤ 1 000 000, 0 ≤ a, b ≤ 109) — the length of the array, the cost of removing a single element in the first operation and the cost of changing an element, respectively. The second line contains n integers ai (2 ≤ ai ≤ 109) — elements of the array. Output Print a single number — the minimum cost of changes needed to obtain an array, such that the greatest common divisor of all its elements is greater than 1. Examples Input 3 1 4 4 2 3 Output 1 Input 5 3 2 5 17 13 5 6 Output 8 Input 8 3 4 3 7 5 4 3 12 9 4 Output 13 Note In the first sample the optimal way is to remove number 3 and pay 1 coin for it. In the second sample you need to remove a segment [17, 13] and then decrease number 6. The cost of these changes is equal to 2·3 + 2 = 8 coins. Submitted Solution: ``` from itertools import accumulate from fractions import gcd import math n, a, b = [int(x) for x in input().split()] A = [int(x) for x in input().split()] N = math.ceil(10 ** 4.5) sqN = math.ceil(N ** 0.5) isprime = [True for i in range(N+1)] isprime[0], isprime[1] = False, False for p in range(2, sqN + 1): if isprime[p]: for i in range(p ** 2, N+1, p): isprime[i] = False primes = [p for p in range(2, N+1) if isprime[p]] def div(n): dividers = [] for p in primes: if n % p == 0: dividers.append(p) while n % p == 0: n //= p if n == 1: break else: dividers.append(n) return dividers L = {p: 0 for p in div(A[0]-1) + div(A[0]) + div(A[0]+1) + div(A[-1]-1) + div(A[-1]) + div(A[-1]+1)} print(L) R = {p: n*a for p in L} def dynamic_update(D, m): D1 = {} for p in D: if (m-1) % p == 0: D1[p] = D[p] + b - a if (m+1) % p == 0: D1[p] = D[p] + b - a if m % p == 0: D1[p] = D[p] - a return D1 def min_compare(D1, D2): return {p: min(D2.get(p, math.inf), D1[p]) for p in D1} B = accumulate([L] + A, dynamic_update) A.reverse() C = accumulate([R] + A, dynamic_update) C1 = list(accumulate(C, min_compare)) ans = min(min(D[p] + C1[-k-1][p] for p in D) for k, D in enumerate(B)) print(ans) ``` No
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given array ai of length n. You may consecutively apply two operations to this array: * remove some subsegment (continuous subsequence) of length m < n and pay for it m·a coins; * change some elements of the array by at most 1, and pay b coins for each change. Please note that each of operations may be applied at most once (and may be not applied at all) so you can remove only one segment and each number may be changed (increased or decreased) by at most 1. Also note, that you are not allowed to delete the whole array. Your goal is to calculate the minimum number of coins that you need to spend in order to make the greatest common divisor of the elements of the resulting array be greater than 1. Input The first line of the input contains integers n, a and b (1 ≤ n ≤ 1 000 000, 0 ≤ a, b ≤ 109) — the length of the array, the cost of removing a single element in the first operation and the cost of changing an element, respectively. The second line contains n integers ai (2 ≤ ai ≤ 109) — elements of the array. Output Print a single number — the minimum cost of changes needed to obtain an array, such that the greatest common divisor of all its elements is greater than 1. Examples Input 3 1 4 4 2 3 Output 1 Input 5 3 2 5 17 13 5 6 Output 8 Input 8 3 4 3 7 5 4 3 12 9 4 Output 13 Note In the first sample the optimal way is to remove number 3 and pay 1 coin for it. In the second sample you need to remove a segment [17, 13] and then decrease number 6. The cost of these changes is equal to 2·3 + 2 = 8 coins. Submitted Solution: ``` def gharbal(n): L=[1]*(n+1) for p in range(2,int(n**0.5)+1): if L[p]: for i in range(p**2,n+1): L[i]=0 for i in range(2,n+1): if L[i]: yield i return n,x,y=map(int,input().split()) z=min(x,y) score=list(map(int,input().split())) out=[] for p in gharbal(max(score)+1): a=b=0 for i in score: c=i%p if c==0: a+=1 if c==p-1: b+=1 d=n-(a+b) out.append(z*b+d*x) print(min(out)) ``` No
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given array ai of length n. You may consecutively apply two operations to this array: * remove some subsegment (continuous subsequence) of length m < n and pay for it m·a coins; * change some elements of the array by at most 1, and pay b coins for each change. Please note that each of operations may be applied at most once (and may be not applied at all) so you can remove only one segment and each number may be changed (increased or decreased) by at most 1. Also note, that you are not allowed to delete the whole array. Your goal is to calculate the minimum number of coins that you need to spend in order to make the greatest common divisor of the elements of the resulting array be greater than 1. Input The first line of the input contains integers n, a and b (1 ≤ n ≤ 1 000 000, 0 ≤ a, b ≤ 109) — the length of the array, the cost of removing a single element in the first operation and the cost of changing an element, respectively. The second line contains n integers ai (2 ≤ ai ≤ 109) — elements of the array. Output Print a single number — the minimum cost of changes needed to obtain an array, such that the greatest common divisor of all its elements is greater than 1. Examples Input 3 1 4 4 2 3 Output 1 Input 5 3 2 5 17 13 5 6 Output 8 Input 8 3 4 3 7 5 4 3 12 9 4 Output 13 Note In the first sample the optimal way is to remove number 3 and pay 1 coin for it. In the second sample you need to remove a segment [17, 13] and then decrease number 6. The cost of these changes is equal to 2·3 + 2 = 8 coins. Submitted Solution: ``` from itertools import accumulate from fractions import gcd import math n, a, b = [int(x) for x in input().split()] A = [int(x) for x in input().split()] N = math.ceil(10 ** 4.5) sqN = math.ceil(N ** 0.5) isprime = [True for i in range(N+1)] isprime[0], isprime[1] = False, False for p in range(2, sqN + 1): if isprime[p]: for i in range(p ** 2, N+1, p): isprime[i] = False check = lambda x, p: ((x-1)%p == 0) or (x%p == 0) or ((x+1)%p == 0) L = {p: 0 for p in range(N+1) if isprime[p] and check(A[0], p)} R = {p: n*a for p in range(N+1) if isprime[p] and check(A[-1], p)} def dynamic_update(D, m): D1 = {} for p in D: if (m-1) % p == 0: D1[p] = D[p] + b - a if (m+1) % p == 0: D1[p] = D[p] + b - a if m % p == 0: D1[p] = D[p] - a return D1 def min_compare(D1, D2): return {p: min(D2[p], D1[p]) for p in D2} B = accumulate([L] + A, dynamic_update) A.reverse() C = accumulate([R] + A, dynamic_update) C1 = list(accumulate(C, min_compare)) ans = min(min(D[p] + C1[-k-1].get(p, math.inf) for p in D) for k, D in enumerate(B)) print(ans) ``` No
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given array ai of length n. You may consecutively apply two operations to this array: * remove some subsegment (continuous subsequence) of length m < n and pay for it m·a coins; * change some elements of the array by at most 1, and pay b coins for each change. Please note that each of operations may be applied at most once (and may be not applied at all) so you can remove only one segment and each number may be changed (increased or decreased) by at most 1. Also note, that you are not allowed to delete the whole array. Your goal is to calculate the minimum number of coins that you need to spend in order to make the greatest common divisor of the elements of the resulting array be greater than 1. Input The first line of the input contains integers n, a and b (1 ≤ n ≤ 1 000 000, 0 ≤ a, b ≤ 109) — the length of the array, the cost of removing a single element in the first operation and the cost of changing an element, respectively. The second line contains n integers ai (2 ≤ ai ≤ 109) — elements of the array. Output Print a single number — the minimum cost of changes needed to obtain an array, such that the greatest common divisor of all its elements is greater than 1. Examples Input 3 1 4 4 2 3 Output 1 Input 5 3 2 5 17 13 5 6 Output 8 Input 8 3 4 3 7 5 4 3 12 9 4 Output 13 Note In the first sample the optimal way is to remove number 3 and pay 1 coin for it. In the second sample you need to remove a segment [17, 13] and then decrease number 6. The cost of these changes is equal to 2·3 + 2 = 8 coins. Submitted Solution: ``` #!/usr/bin/python3 ''' Created on Feb 04, 2016 @author: kate ''' def nod(a, b): while a != b: if a > b: a = a - b else: b = b - a return a def check(n, a): if n == 1: print (0) return False return True def get_sum(elem, mas, a, b): sum = 0 a_count = 0 a_flag = False b_flag = False for i in range(len(mas)): if nod(elem, mas[i]) > 1: if elem > mas[i]: return False if a_count > 0: a_flag = True sum = a_count * a else: if not a_flag: a_count += 1 elif not b_flag: b_flag = True sum += b else: return False if not a_flag and a_count > 0: sum = a_count * a return sum n, a, b = [int(x) for x in input().split()] if check(n, a): mas = [int(x) for x in input().split()] sum = False for elem in mas: current_sum = get_sum(elem, mas, a, b) if current_sum: if sum == False or sum > current_sum: sum = current_sum print(sum or 0) ``` No
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Provide tags and a correct Python 3 solution for this coding contest problem. Bessie the cow and her best friend Elsie each received a sliding puzzle on Pi Day. Their puzzles consist of a 2 × 2 grid and three tiles labeled 'A', 'B', and 'C'. The three tiles sit on top of the grid, leaving one grid cell empty. To make a move, Bessie or Elsie can slide a tile adjacent to the empty cell into the empty cell as shown below: <image> In order to determine if they are truly Best Friends For Life (BFFLs), Bessie and Elsie would like to know if there exists a sequence of moves that takes their puzzles to the same configuration (moves can be performed in both puzzles). Two puzzles are considered to be in the same configuration if each tile is on top of the same grid cell in both puzzles. Since the tiles are labeled with letters, rotations and reflections are not allowed. Input The first two lines of the input consist of a 2 × 2 grid describing the initial configuration of Bessie's puzzle. The next two lines contain a 2 × 2 grid describing the initial configuration of Elsie's puzzle. The positions of the tiles are labeled 'A', 'B', and 'C', while the empty cell is labeled 'X'. It's guaranteed that both puzzles contain exactly one tile with each letter and exactly one empty position. Output Output "YES"(without quotes) if the puzzles can reach the same configuration (and Bessie and Elsie are truly BFFLs). Otherwise, print "NO" (without quotes). Examples Input AB XC XB AC Output YES Input AB XC AC BX Output NO Note The solution to the first sample is described by the image. All Bessie needs to do is slide her 'A' tile down. In the second sample, the two puzzles can never be in the same configuration. Perhaps Bessie and Elsie are not meant to be friends after all... Tags: brute force, constructive algorithms, implementation Correct Solution: ``` a = input() b = input() c = input() d = input() s = list(a + b[1] + b[0]) t = list(c + d[1] + d[0]) s.remove('X') t.remove('X') for i in range(5): t = t[1:] + [t[0]] if s == t: print("YES") break else: print("NO") ```
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Provide tags and a correct Python 3 solution for this coding contest problem. Bessie the cow and her best friend Elsie each received a sliding puzzle on Pi Day. Their puzzles consist of a 2 × 2 grid and three tiles labeled 'A', 'B', and 'C'. The three tiles sit on top of the grid, leaving one grid cell empty. To make a move, Bessie or Elsie can slide a tile adjacent to the empty cell into the empty cell as shown below: <image> In order to determine if they are truly Best Friends For Life (BFFLs), Bessie and Elsie would like to know if there exists a sequence of moves that takes their puzzles to the same configuration (moves can be performed in both puzzles). Two puzzles are considered to be in the same configuration if each tile is on top of the same grid cell in both puzzles. Since the tiles are labeled with letters, rotations and reflections are not allowed. Input The first two lines of the input consist of a 2 × 2 grid describing the initial configuration of Bessie's puzzle. The next two lines contain a 2 × 2 grid describing the initial configuration of Elsie's puzzle. The positions of the tiles are labeled 'A', 'B', and 'C', while the empty cell is labeled 'X'. It's guaranteed that both puzzles contain exactly one tile with each letter and exactly one empty position. Output Output "YES"(without quotes) if the puzzles can reach the same configuration (and Bessie and Elsie are truly BFFLs). Otherwise, print "NO" (without quotes). Examples Input AB XC XB AC Output YES Input AB XC AC BX Output NO Note The solution to the first sample is described by the image. All Bessie needs to do is slide her 'A' tile down. In the second sample, the two puzzles can never be in the same configuration. Perhaps Bessie and Elsie are not meant to be friends after all... Tags: brute force, constructive algorithms, implementation Correct Solution: ``` count = 12 ans = False first = [list(input())] first.append(list(input())) second = [list(input())] second.append(list(input())) for i in range(count): if first == second: ans = True break if first[0][0] == 'X': first[0][0], first[0][1] = first[0][1], first[0][0] elif first[0][1] == 'X': first[0][1], first[1][1] = first[1][1], first[0][1] elif first[1][1] == 'X': first[1][1], first[1][0] = first[1][0], first[1][1] elif first[1][0] == 'X': first[1][0], first[0][0] = first[0][0], first[1][0] if ans: print('YES') else: print('NO') ```
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Provide tags and a correct Python 3 solution for this coding contest problem. Bessie the cow and her best friend Elsie each received a sliding puzzle on Pi Day. Their puzzles consist of a 2 × 2 grid and three tiles labeled 'A', 'B', and 'C'. The three tiles sit on top of the grid, leaving one grid cell empty. To make a move, Bessie or Elsie can slide a tile adjacent to the empty cell into the empty cell as shown below: <image> In order to determine if they are truly Best Friends For Life (BFFLs), Bessie and Elsie would like to know if there exists a sequence of moves that takes their puzzles to the same configuration (moves can be performed in both puzzles). Two puzzles are considered to be in the same configuration if each tile is on top of the same grid cell in both puzzles. Since the tiles are labeled with letters, rotations and reflections are not allowed. Input The first two lines of the input consist of a 2 × 2 grid describing the initial configuration of Bessie's puzzle. The next two lines contain a 2 × 2 grid describing the initial configuration of Elsie's puzzle. The positions of the tiles are labeled 'A', 'B', and 'C', while the empty cell is labeled 'X'. It's guaranteed that both puzzles contain exactly one tile with each letter and exactly one empty position. Output Output "YES"(without quotes) if the puzzles can reach the same configuration (and Bessie and Elsie are truly BFFLs). Otherwise, print "NO" (without quotes). Examples Input AB XC XB AC Output YES Input AB XC AC BX Output NO Note The solution to the first sample is described by the image. All Bessie needs to do is slide her 'A' tile down. In the second sample, the two puzzles can never be in the same configuration. Perhaps Bessie and Elsie are not meant to be friends after all... Tags: brute force, constructive algorithms, implementation Correct Solution: ``` a = input() a = a + input()[::-1] a = a.replace('X','') b = input() b = b + input()[::-1] b = b.replace('X','') b = b * 2 if b.find(a) == -1: print('NO') else: print('YES') ```
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Provide tags and a correct Python 3 solution for this coding contest problem. Bessie the cow and her best friend Elsie each received a sliding puzzle on Pi Day. Their puzzles consist of a 2 × 2 grid and three tiles labeled 'A', 'B', and 'C'. The three tiles sit on top of the grid, leaving one grid cell empty. To make a move, Bessie or Elsie can slide a tile adjacent to the empty cell into the empty cell as shown below: <image> In order to determine if they are truly Best Friends For Life (BFFLs), Bessie and Elsie would like to know if there exists a sequence of moves that takes their puzzles to the same configuration (moves can be performed in both puzzles). Two puzzles are considered to be in the same configuration if each tile is on top of the same grid cell in both puzzles. Since the tiles are labeled with letters, rotations and reflections are not allowed. Input The first two lines of the input consist of a 2 × 2 grid describing the initial configuration of Bessie's puzzle. The next two lines contain a 2 × 2 grid describing the initial configuration of Elsie's puzzle. The positions of the tiles are labeled 'A', 'B', and 'C', while the empty cell is labeled 'X'. It's guaranteed that both puzzles contain exactly one tile with each letter and exactly one empty position. Output Output "YES"(without quotes) if the puzzles can reach the same configuration (and Bessie and Elsie are truly BFFLs). Otherwise, print "NO" (without quotes). Examples Input AB XC XB AC Output YES Input AB XC AC BX Output NO Note The solution to the first sample is described by the image. All Bessie needs to do is slide her 'A' tile down. In the second sample, the two puzzles can never be in the same configuration. Perhaps Bessie and Elsie are not meant to be friends after all... Tags: brute force, constructive algorithms, implementation Correct Solution: ``` #!/usr/bin/python3 def main(): a = input() + "".join(reversed(input())) b = input() + "".join(reversed(input())) a = a[:a.find("X")] + a[a.find("X") + 1:] b = b[:b.find("X")] + b[b.find("X") + 1:] for i in range(3): if a[i:] + a[:i] == b: return True return False if main(): print("YES") else: print("NO") ```
90,551
Provide tags and a correct Python 3 solution for this coding contest problem. Bessie the cow and her best friend Elsie each received a sliding puzzle on Pi Day. Their puzzles consist of a 2 × 2 grid and three tiles labeled 'A', 'B', and 'C'. The three tiles sit on top of the grid, leaving one grid cell empty. To make a move, Bessie or Elsie can slide a tile adjacent to the empty cell into the empty cell as shown below: <image> In order to determine if they are truly Best Friends For Life (BFFLs), Bessie and Elsie would like to know if there exists a sequence of moves that takes their puzzles to the same configuration (moves can be performed in both puzzles). Two puzzles are considered to be in the same configuration if each tile is on top of the same grid cell in both puzzles. Since the tiles are labeled with letters, rotations and reflections are not allowed. Input The first two lines of the input consist of a 2 × 2 grid describing the initial configuration of Bessie's puzzle. The next two lines contain a 2 × 2 grid describing the initial configuration of Elsie's puzzle. The positions of the tiles are labeled 'A', 'B', and 'C', while the empty cell is labeled 'X'. It's guaranteed that both puzzles contain exactly one tile with each letter and exactly one empty position. Output Output "YES"(without quotes) if the puzzles can reach the same configuration (and Bessie and Elsie are truly BFFLs). Otherwise, print "NO" (without quotes). Examples Input AB XC XB AC Output YES Input AB XC AC BX Output NO Note The solution to the first sample is described by the image. All Bessie needs to do is slide her 'A' tile down. In the second sample, the two puzzles can never be in the same configuration. Perhaps Bessie and Elsie are not meant to be friends after all... Tags: brute force, constructive algorithms, implementation Correct Solution: ``` def find_order(A, B): d = dict() i = 0 if A[0] != 'X': d[i] = A[0] i += 1 if A[1] != 'X': d[i] = A[1] i += 1 if B[1] != 'X': d[i] = B[1] i += 1 if B[0] != 'X': d[i] = B[0] i += 1 return d a = input() b = input() c = input() d = input() m = find_order(a, b) n = find_order(c, d) m[3] = m[0] m[4] = m[1] if m[0] == n[0]: if m[1] == n[1] and m[2] == n[2]: print('YES') else: print('NO') elif m[1] == n[0]: if m[2] == n[1] and m[3] == n[2]: print('YES') else: print('NO') elif m[2] == n[0]: if m[3] == n[1] and m[4] == n[2]: print('YES') else: print('NO') ```
90,552
Provide tags and a correct Python 3 solution for this coding contest problem. Bessie the cow and her best friend Elsie each received a sliding puzzle on Pi Day. Their puzzles consist of a 2 × 2 grid and three tiles labeled 'A', 'B', and 'C'. The three tiles sit on top of the grid, leaving one grid cell empty. To make a move, Bessie or Elsie can slide a tile adjacent to the empty cell into the empty cell as shown below: <image> In order to determine if they are truly Best Friends For Life (BFFLs), Bessie and Elsie would like to know if there exists a sequence of moves that takes their puzzles to the same configuration (moves can be performed in both puzzles). Two puzzles are considered to be in the same configuration if each tile is on top of the same grid cell in both puzzles. Since the tiles are labeled with letters, rotations and reflections are not allowed. Input The first two lines of the input consist of a 2 × 2 grid describing the initial configuration of Bessie's puzzle. The next two lines contain a 2 × 2 grid describing the initial configuration of Elsie's puzzle. The positions of the tiles are labeled 'A', 'B', and 'C', while the empty cell is labeled 'X'. It's guaranteed that both puzzles contain exactly one tile with each letter and exactly one empty position. Output Output "YES"(without quotes) if the puzzles can reach the same configuration (and Bessie and Elsie are truly BFFLs). Otherwise, print "NO" (without quotes). Examples Input AB XC XB AC Output YES Input AB XC AC BX Output NO Note The solution to the first sample is described by the image. All Bessie needs to do is slide her 'A' tile down. In the second sample, the two puzzles can never be in the same configuration. Perhaps Bessie and Elsie are not meant to be friends after all... Tags: brute force, constructive algorithms, implementation Correct Solution: ``` s1 = "" s2 = "" a = input() b = input() c = input() d = input() s1 = list(a + b[1] + b[0]) s2 = list(c + d[1] + d[0]) t = s1.index('X') if t != 3: s1 = s1[:t] + s1[t+1:] else: s1 = s1[:3] t = s2.index('X') if t != 3: s2 = s2[:t] + s2[t+1:] else: s2 = s2[:3] if s1[0] + s1[1] + s1[2] == s2[0] + s2[1] + s2[2] or s1[1] + s1[2] + s1[0] == s2[0] + s2[1] + s2[2] or s1[2] + s1[0] + s1[1] == s2[0] + s2[1] + s2[2]: print("YES") else: print("NO") ```
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Provide tags and a correct Python 3 solution for this coding contest problem. Bessie the cow and her best friend Elsie each received a sliding puzzle on Pi Day. Their puzzles consist of a 2 × 2 grid and three tiles labeled 'A', 'B', and 'C'. The three tiles sit on top of the grid, leaving one grid cell empty. To make a move, Bessie or Elsie can slide a tile adjacent to the empty cell into the empty cell as shown below: <image> In order to determine if they are truly Best Friends For Life (BFFLs), Bessie and Elsie would like to know if there exists a sequence of moves that takes their puzzles to the same configuration (moves can be performed in both puzzles). Two puzzles are considered to be in the same configuration if each tile is on top of the same grid cell in both puzzles. Since the tiles are labeled with letters, rotations and reflections are not allowed. Input The first two lines of the input consist of a 2 × 2 grid describing the initial configuration of Bessie's puzzle. The next two lines contain a 2 × 2 grid describing the initial configuration of Elsie's puzzle. The positions of the tiles are labeled 'A', 'B', and 'C', while the empty cell is labeled 'X'. It's guaranteed that both puzzles contain exactly one tile with each letter and exactly one empty position. Output Output "YES"(without quotes) if the puzzles can reach the same configuration (and Bessie and Elsie are truly BFFLs). Otherwise, print "NO" (without quotes). Examples Input AB XC XB AC Output YES Input AB XC AC BX Output NO Note The solution to the first sample is described by the image. All Bessie needs to do is slide her 'A' tile down. In the second sample, the two puzzles can never be in the same configuration. Perhaps Bessie and Elsie are not meant to be friends after all... Tags: brute force, constructive algorithms, implementation Correct Solution: ``` f = lambda: 'ABC' in 2 * (input()+input()[::-1]).replace('X', '') print('NO' if f()^f() else 'YES') ```
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Provide tags and a correct Python 3 solution for this coding contest problem. Bessie the cow and her best friend Elsie each received a sliding puzzle on Pi Day. Their puzzles consist of a 2 × 2 grid and three tiles labeled 'A', 'B', and 'C'. The three tiles sit on top of the grid, leaving one grid cell empty. To make a move, Bessie or Elsie can slide a tile adjacent to the empty cell into the empty cell as shown below: <image> In order to determine if they are truly Best Friends For Life (BFFLs), Bessie and Elsie would like to know if there exists a sequence of moves that takes their puzzles to the same configuration (moves can be performed in both puzzles). Two puzzles are considered to be in the same configuration if each tile is on top of the same grid cell in both puzzles. Since the tiles are labeled with letters, rotations and reflections are not allowed. Input The first two lines of the input consist of a 2 × 2 grid describing the initial configuration of Bessie's puzzle. The next two lines contain a 2 × 2 grid describing the initial configuration of Elsie's puzzle. The positions of the tiles are labeled 'A', 'B', and 'C', while the empty cell is labeled 'X'. It's guaranteed that both puzzles contain exactly one tile with each letter and exactly one empty position. Output Output "YES"(without quotes) if the puzzles can reach the same configuration (and Bessie and Elsie are truly BFFLs). Otherwise, print "NO" (without quotes). Examples Input AB XC XB AC Output YES Input AB XC AC BX Output NO Note The solution to the first sample is described by the image. All Bessie needs to do is slide her 'A' tile down. In the second sample, the two puzzles can never be in the same configuration. Perhaps Bessie and Elsie are not meant to be friends after all... Tags: brute force, constructive algorithms, implementation Correct Solution: ``` s1 = input() + input()[::-1] s2 = input() + input()[::-1] s1 = s1[:s1.find('X')] + s1[s1.find('X') + 1:] s2 = s2[:s2.find('X')] + s2[s2.find('X') + 1:] flag = False for i in range(3): if s1 == s2: flag = True break s1 = s1[-1] + s1[:-1] print('YES' if flag else 'NO') ```
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Bessie the cow and her best friend Elsie each received a sliding puzzle on Pi Day. Their puzzles consist of a 2 × 2 grid and three tiles labeled 'A', 'B', and 'C'. The three tiles sit on top of the grid, leaving one grid cell empty. To make a move, Bessie or Elsie can slide a tile adjacent to the empty cell into the empty cell as shown below: <image> In order to determine if they are truly Best Friends For Life (BFFLs), Bessie and Elsie would like to know if there exists a sequence of moves that takes their puzzles to the same configuration (moves can be performed in both puzzles). Two puzzles are considered to be in the same configuration if each tile is on top of the same grid cell in both puzzles. Since the tiles are labeled with letters, rotations and reflections are not allowed. Input The first two lines of the input consist of a 2 × 2 grid describing the initial configuration of Bessie's puzzle. The next two lines contain a 2 × 2 grid describing the initial configuration of Elsie's puzzle. The positions of the tiles are labeled 'A', 'B', and 'C', while the empty cell is labeled 'X'. It's guaranteed that both puzzles contain exactly one tile with each letter and exactly one empty position. Output Output "YES"(without quotes) if the puzzles can reach the same configuration (and Bessie and Elsie are truly BFFLs). Otherwise, print "NO" (without quotes). Examples Input AB XC XB AC Output YES Input AB XC AC BX Output NO Note The solution to the first sample is described by the image. All Bessie needs to do is slide her 'A' tile down. In the second sample, the two puzzles can never be in the same configuration. Perhaps Bessie and Elsie are not meant to be friends after all... Submitted Solution: ``` a1 = input() a2 = input() b1 = input() b2 = input() bel = [a1,a2] el = [b1,b2] checker = False for i in range(100): if not( a1 == b1 and a2 == b2): if 'X' in a1: if a1.find('X') == 0: a1 = a2[0]+a1[1] a2 = 'X'+a2[1] else: a1 = 'X'+a1[0] else: if a2.find('X') == 0: a2 = a2[1] + 'X' else: a2 = a2[0] + a1[1] a1 = a1[0] +'X' else: checker = True break if checker == True: print('YES') else: print('NO') ``` Yes
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Bessie the cow and her best friend Elsie each received a sliding puzzle on Pi Day. Their puzzles consist of a 2 × 2 grid and three tiles labeled 'A', 'B', and 'C'. The three tiles sit on top of the grid, leaving one grid cell empty. To make a move, Bessie or Elsie can slide a tile adjacent to the empty cell into the empty cell as shown below: <image> In order to determine if they are truly Best Friends For Life (BFFLs), Bessie and Elsie would like to know if there exists a sequence of moves that takes their puzzles to the same configuration (moves can be performed in both puzzles). Two puzzles are considered to be in the same configuration if each tile is on top of the same grid cell in both puzzles. Since the tiles are labeled with letters, rotations and reflections are not allowed. Input The first two lines of the input consist of a 2 × 2 grid describing the initial configuration of Bessie's puzzle. The next two lines contain a 2 × 2 grid describing the initial configuration of Elsie's puzzle. The positions of the tiles are labeled 'A', 'B', and 'C', while the empty cell is labeled 'X'. It's guaranteed that both puzzles contain exactly one tile with each letter and exactly one empty position. Output Output "YES"(without quotes) if the puzzles can reach the same configuration (and Bessie and Elsie are truly BFFLs). Otherwise, print "NO" (without quotes). Examples Input AB XC XB AC Output YES Input AB XC AC BX Output NO Note The solution to the first sample is described by the image. All Bessie needs to do is slide her 'A' tile down. In the second sample, the two puzzles can never be in the same configuration. Perhaps Bessie and Elsie are not meant to be friends after all... Submitted Solution: ``` list1 = [(i)for i in input()] list2 = [(i)for i in input()] list3 = [(i)for i in input()] list4 = [(i)for i in input()] chars1 = "" chars2 = "" if list1[0]!="X": chars1+=list1[0] if list1[1]!="X": chars1+=list1[1] if list2[1]!="X": chars1+=list2[1] if list2[0]!="X": chars1+=list2[0] chars1*=2 if list3[0]!="X": chars2+=list3[0] if list3[1]!="X": chars2+=list3[1] if list4[1]!="X": chars2+=list4[1] if list4[0]!="X": chars2+=list4[0] if chars2 in chars1: print("YES") else: print("NO") ``` Yes
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Bessie the cow and her best friend Elsie each received a sliding puzzle on Pi Day. Their puzzles consist of a 2 × 2 grid and three tiles labeled 'A', 'B', and 'C'. The three tiles sit on top of the grid, leaving one grid cell empty. To make a move, Bessie or Elsie can slide a tile adjacent to the empty cell into the empty cell as shown below: <image> In order to determine if they are truly Best Friends For Life (BFFLs), Bessie and Elsie would like to know if there exists a sequence of moves that takes their puzzles to the same configuration (moves can be performed in both puzzles). Two puzzles are considered to be in the same configuration if each tile is on top of the same grid cell in both puzzles. Since the tiles are labeled with letters, rotations and reflections are not allowed. Input The first two lines of the input consist of a 2 × 2 grid describing the initial configuration of Bessie's puzzle. The next two lines contain a 2 × 2 grid describing the initial configuration of Elsie's puzzle. The positions of the tiles are labeled 'A', 'B', and 'C', while the empty cell is labeled 'X'. It's guaranteed that both puzzles contain exactly one tile with each letter and exactly one empty position. Output Output "YES"(without quotes) if the puzzles can reach the same configuration (and Bessie and Elsie are truly BFFLs). Otherwise, print "NO" (without quotes). Examples Input AB XC XB AC Output YES Input AB XC AC BX Output NO Note The solution to the first sample is described by the image. All Bessie needs to do is slide her 'A' tile down. In the second sample, the two puzzles can never be in the same configuration. Perhaps Bessie and Elsie are not meant to be friends after all... Submitted Solution: ``` s1=input() s2=input() s3=input() s4=input() s11=s1+s2[::-1] s22=s3+s4[::-1] k1="" k2="" for i in range(4): if s11[i]!='X': k1+=s11[i] for i in range(4): if s22[i]!='X': k2+=s22[i] k1=k1*3 #print(k1) #print(k2) if k2 in k1: print('YES') else: print('NO') ``` Yes
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Bessie the cow and her best friend Elsie each received a sliding puzzle on Pi Day. Their puzzles consist of a 2 × 2 grid and three tiles labeled 'A', 'B', and 'C'. The three tiles sit on top of the grid, leaving one grid cell empty. To make a move, Bessie or Elsie can slide a tile adjacent to the empty cell into the empty cell as shown below: <image> In order to determine if they are truly Best Friends For Life (BFFLs), Bessie and Elsie would like to know if there exists a sequence of moves that takes their puzzles to the same configuration (moves can be performed in both puzzles). Two puzzles are considered to be in the same configuration if each tile is on top of the same grid cell in both puzzles. Since the tiles are labeled with letters, rotations and reflections are not allowed. Input The first two lines of the input consist of a 2 × 2 grid describing the initial configuration of Bessie's puzzle. The next two lines contain a 2 × 2 grid describing the initial configuration of Elsie's puzzle. The positions of the tiles are labeled 'A', 'B', and 'C', while the empty cell is labeled 'X'. It's guaranteed that both puzzles contain exactly one tile with each letter and exactly one empty position. Output Output "YES"(without quotes) if the puzzles can reach the same configuration (and Bessie and Elsie are truly BFFLs). Otherwise, print "NO" (without quotes). Examples Input AB XC XB AC Output YES Input AB XC AC BX Output NO Note The solution to the first sample is described by the image. All Bessie needs to do is slide her 'A' tile down. In the second sample, the two puzzles can never be in the same configuration. Perhaps Bessie and Elsie are not meant to be friends after all... Submitted Solution: ``` per1 = input() per2 = input() per3 = input() per4 = input() s= [] s.append(per1[0]) s.append (per1[1]) s.append (per2[1]) s.append (per2[0]) for i in range(len(s)): if s[i] == 'X': s.pop(i) break d= [] d.append(per3[0]) d.append (per3[1]) d.append (per4[1]) d.append (per4[0]) for i in range(len(d)): if d[i] == 'X': d.pop(i) break per2 = False for i in range(3): if s != d: t = d.pop(0) d.append(t) else: per2 = True break if per2: print('YES') else: print('NO') ``` Yes
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Bessie the cow and her best friend Elsie each received a sliding puzzle on Pi Day. Their puzzles consist of a 2 × 2 grid and three tiles labeled 'A', 'B', and 'C'. The three tiles sit on top of the grid, leaving one grid cell empty. To make a move, Bessie or Elsie can slide a tile adjacent to the empty cell into the empty cell as shown below: <image> In order to determine if they are truly Best Friends For Life (BFFLs), Bessie and Elsie would like to know if there exists a sequence of moves that takes their puzzles to the same configuration (moves can be performed in both puzzles). Two puzzles are considered to be in the same configuration if each tile is on top of the same grid cell in both puzzles. Since the tiles are labeled with letters, rotations and reflections are not allowed. Input The first two lines of the input consist of a 2 × 2 grid describing the initial configuration of Bessie's puzzle. The next two lines contain a 2 × 2 grid describing the initial configuration of Elsie's puzzle. The positions of the tiles are labeled 'A', 'B', and 'C', while the empty cell is labeled 'X'. It's guaranteed that both puzzles contain exactly one tile with each letter and exactly one empty position. Output Output "YES"(without quotes) if the puzzles can reach the same configuration (and Bessie and Elsie are truly BFFLs). Otherwise, print "NO" (without quotes). Examples Input AB XC XB AC Output YES Input AB XC AC BX Output NO Note The solution to the first sample is described by the image. All Bessie needs to do is slide her 'A' tile down. In the second sample, the two puzzles can never be in the same configuration. Perhaps Bessie and Elsie are not meant to be friends after all... Submitted Solution: ``` s=str(input()) s1=str(input()) s2=str(input()) s3=str(input()) e='' f='' flag=0 for i in range(0,len(s)): if(s[i]!='X'): e=e+s[i] for i in range(0,len(s1)): if(s1[i]!='X'): f=f+s1[i] if((e=='AB' and f=='C') or (e=='BC' and f=='A') or (e=='CA' and f=='B') or (e=='A' and f=='CB') or (e=='B' and f=='AC')or(e=='C' and f=='BA')): pass else: flag=1 if(flag==0): e='' f='' for i in range(0,len(s2)): if(s2[i]!='X'): e=e+s2[i] for i in range(0,len(s3)): if(s3[i]!='X'): f=f+s3[i] if(e=='AB' and f=='C' or (e=='BC' and f=='A') or (e=='CA' and f=='B') or (e=='A' and f=='CB') or (e=='B' and f=='AC')or(e=='C' and f=='BA')): pass else: flag=1 if(flag==0): print('YES') else: print('NO') ``` No
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Bessie the cow and her best friend Elsie each received a sliding puzzle on Pi Day. Their puzzles consist of a 2 × 2 grid and three tiles labeled 'A', 'B', and 'C'. The three tiles sit on top of the grid, leaving one grid cell empty. To make a move, Bessie or Elsie can slide a tile adjacent to the empty cell into the empty cell as shown below: <image> In order to determine if they are truly Best Friends For Life (BFFLs), Bessie and Elsie would like to know if there exists a sequence of moves that takes their puzzles to the same configuration (moves can be performed in both puzzles). Two puzzles are considered to be in the same configuration if each tile is on top of the same grid cell in both puzzles. Since the tiles are labeled with letters, rotations and reflections are not allowed. Input The first two lines of the input consist of a 2 × 2 grid describing the initial configuration of Bessie's puzzle. The next two lines contain a 2 × 2 grid describing the initial configuration of Elsie's puzzle. The positions of the tiles are labeled 'A', 'B', and 'C', while the empty cell is labeled 'X'. It's guaranteed that both puzzles contain exactly one tile with each letter and exactly one empty position. Output Output "YES"(without quotes) if the puzzles can reach the same configuration (and Bessie and Elsie are truly BFFLs). Otherwise, print "NO" (without quotes). Examples Input AB XC XB AC Output YES Input AB XC AC BX Output NO Note The solution to the first sample is described by the image. All Bessie needs to do is slide her 'A' tile down. In the second sample, the two puzzles can never be in the same configuration. Perhaps Bessie and Elsie are not meant to be friends after all... Submitted Solution: ``` a = [list(input()), list(input())] b = [list(input()), list(input())] def nxt(a): x, y = 0, 0 for i in range(2): for j in range(2): if a[i][j] == 'X': x, y = i, j if (x, y) == (0, 0): a[x][y] = a[x+1][y] a[x+1][y] = 'X' elif (x, y) == (0, 1): a[x][y] = a[x][y-1] a[x][y-1] = 'X' elif (x, y) == (1, 0): a[x][y] = a[x][y+1] a[x][y+1] = 'X' else: a[x][y] = a[x-1][y] a[x-1][y] = 'X' return a def prv(a): x, y = 0, 0 for i in range(2): for j in range(2): if a[i][j] == 'X': x, y = i, j if (x, y) == (0, 0): a[x][y] = a[x][y+1] a[x][y+1] = 'X' elif (x, y) == (0, 1): a[x][y] = a[x+1][y] a[x+1][y] = 'X' elif (x, y) == (1, 0): a[x][y] = a[x-1][y] a[x-1][y] = 'X' else: a[x][y] = a[x][y-1] a[x][y-1] = 'X' return a c = b[:] if b == a: print('YES') else: b = nxt(b) if b == a: print('YES') else: b = nxt(b) if b == a: print('YES') else: b = nxt(b) if b == a: print('YES') else: b = c[:] if b == a: print('YES') else: b = prv(b) if b == a: print('YES') else: b = prv(b) if b == a: print('YES') else: b = prv(b) if b == a: print('YES') else: print('NO') ``` No
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Bessie the cow and her best friend Elsie each received a sliding puzzle on Pi Day. Their puzzles consist of a 2 × 2 grid and three tiles labeled 'A', 'B', and 'C'. The three tiles sit on top of the grid, leaving one grid cell empty. To make a move, Bessie or Elsie can slide a tile adjacent to the empty cell into the empty cell as shown below: <image> In order to determine if they are truly Best Friends For Life (BFFLs), Bessie and Elsie would like to know if there exists a sequence of moves that takes their puzzles to the same configuration (moves can be performed in both puzzles). Two puzzles are considered to be in the same configuration if each tile is on top of the same grid cell in both puzzles. Since the tiles are labeled with letters, rotations and reflections are not allowed. Input The first two lines of the input consist of a 2 × 2 grid describing the initial configuration of Bessie's puzzle. The next two lines contain a 2 × 2 grid describing the initial configuration of Elsie's puzzle. The positions of the tiles are labeled 'A', 'B', and 'C', while the empty cell is labeled 'X'. It's guaranteed that both puzzles contain exactly one tile with each letter and exactly one empty position. Output Output "YES"(without quotes) if the puzzles can reach the same configuration (and Bessie and Elsie are truly BFFLs). Otherwise, print "NO" (without quotes). Examples Input AB XC XB AC Output YES Input AB XC AC BX Output NO Note The solution to the first sample is described by the image. All Bessie needs to do is slide her 'A' tile down. In the second sample, the two puzzles can never be in the same configuration. Perhaps Bessie and Elsie are not meant to be friends after all... Submitted Solution: ``` mas = ["ABXC", "XBAC", "BXAC", "BCAX", "BCXA", "XCBA", "CXBA", "CABX", "CAXB", "XACB", "AXCB", "ABCX"] a = input() a += input() b = input() b += input() if a in mas and b in mas: print("YES") else: print("NO") ``` No
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Bessie the cow and her best friend Elsie each received a sliding puzzle on Pi Day. Their puzzles consist of a 2 × 2 grid and three tiles labeled 'A', 'B', and 'C'. The three tiles sit on top of the grid, leaving one grid cell empty. To make a move, Bessie or Elsie can slide a tile adjacent to the empty cell into the empty cell as shown below: <image> In order to determine if they are truly Best Friends For Life (BFFLs), Bessie and Elsie would like to know if there exists a sequence of moves that takes their puzzles to the same configuration (moves can be performed in both puzzles). Two puzzles are considered to be in the same configuration if each tile is on top of the same grid cell in both puzzles. Since the tiles are labeled with letters, rotations and reflections are not allowed. Input The first two lines of the input consist of a 2 × 2 grid describing the initial configuration of Bessie's puzzle. The next two lines contain a 2 × 2 grid describing the initial configuration of Elsie's puzzle. The positions of the tiles are labeled 'A', 'B', and 'C', while the empty cell is labeled 'X'. It's guaranteed that both puzzles contain exactly one tile with each letter and exactly one empty position. Output Output "YES"(without quotes) if the puzzles can reach the same configuration (and Bessie and Elsie are truly BFFLs). Otherwise, print "NO" (without quotes). Examples Input AB XC XB AC Output YES Input AB XC AC BX Output NO Note The solution to the first sample is described by the image. All Bessie needs to do is slide her 'A' tile down. In the second sample, the two puzzles can never be in the same configuration. Perhaps Bessie and Elsie are not meant to be friends after all... Submitted Solution: ``` s=str(input()) s1=str(input()) s2=str(input()) s3=str(input()) e='' f='' flag=0 for i in range(0,len(s)): if(s[i]!='X'): e=e+s[i] for i in range(0,len(s1)): if(s1[i]!='X'): f=f+s1[i] print(e,f) if((e=='AB' and f=='C') or (e=='BC' and f=='A') or (e=='CA' and f=='B') or (e=='A' and f=='CB') or (e=='B' and f=='AC')or(e=='C' and f=='BA')): pass else: flag=1 if(flag==0): e='' f='' for i in range(0,len(s2)): if(s2[i]!='X'): e=e+s2[i] for i in range(0,len(s3)): if(s3[i]!='X'): f=f+s3[i] if(e=='AB' and f=='C' or (e=='BC' and f=='A') or (e=='CA' and f=='B') or (e=='A' and f=='CB') or (e=='B' and f=='AC')or(e=='C' and f=='BA')): pass else: flag=1 if(flag==0): print('NO') else: print('YES') ``` No
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Provide tags and a correct Python 3 solution for this coding contest problem. Ted has a pineapple. This pineapple is able to bark like a bulldog! At time t (in seconds) it barks for the first time. Then every s seconds after it, it barks twice with 1 second interval. Thus it barks at times t, t + s, t + s + 1, t + 2s, t + 2s + 1, etc. <image> Barney woke up in the morning and wants to eat the pineapple, but he can't eat it when it's barking. Barney plans to eat it at time x (in seconds), so he asked you to tell him if it's gonna bark at that time. Input The first and only line of input contains three integers t, s and x (0 ≤ t, x ≤ 109, 2 ≤ s ≤ 109) — the time the pineapple barks for the first time, the pineapple barking interval, and the time Barney wants to eat the pineapple respectively. Output Print a single "YES" (without quotes) if the pineapple will bark at time x or a single "NO" (without quotes) otherwise in the only line of output. Examples Input 3 10 4 Output NO Input 3 10 3 Output YES Input 3 8 51 Output YES Input 3 8 52 Output YES Note In the first and the second sample cases pineapple will bark at moments 3, 13, 14, ..., so it won't bark at the moment 4 and will bark at the moment 3. In the third and fourth sample cases pineapple will bark at moments 3, 11, 12, 19, 20, 27, 28, 35, 36, 43, 44, 51, 52, 59, ..., so it will bark at both moments 51 and 52. Tags: implementation, math Correct Solution: ``` t, s, x = map(int, input().split()) if (x - 1 == t and s != 1) or t > x: print('NO') elif (x - t) % s == 0 or (x - t) % s == 1: print('YES') else: print('NO') ```
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Provide tags and a correct Python 3 solution for this coding contest problem. Ted has a pineapple. This pineapple is able to bark like a bulldog! At time t (in seconds) it barks for the first time. Then every s seconds after it, it barks twice with 1 second interval. Thus it barks at times t, t + s, t + s + 1, t + 2s, t + 2s + 1, etc. <image> Barney woke up in the morning and wants to eat the pineapple, but he can't eat it when it's barking. Barney plans to eat it at time x (in seconds), so he asked you to tell him if it's gonna bark at that time. Input The first and only line of input contains three integers t, s and x (0 ≤ t, x ≤ 109, 2 ≤ s ≤ 109) — the time the pineapple barks for the first time, the pineapple barking interval, and the time Barney wants to eat the pineapple respectively. Output Print a single "YES" (without quotes) if the pineapple will bark at time x or a single "NO" (without quotes) otherwise in the only line of output. Examples Input 3 10 4 Output NO Input 3 10 3 Output YES Input 3 8 51 Output YES Input 3 8 52 Output YES Note In the first and the second sample cases pineapple will bark at moments 3, 13, 14, ..., so it won't bark at the moment 4 and will bark at the moment 3. In the third and fourth sample cases pineapple will bark at moments 3, 11, 12, 19, 20, 27, 28, 35, 36, 43, 44, 51, 52, 59, ..., so it will bark at both moments 51 and 52. Tags: implementation, math Correct Solution: ``` i = input().split() for j in range(3): i[j]=int(i[j]) if (i[2]+i[1]-i[0])%i[1]==0 and i[2]>=i[0]: print("YES\n") else: i[2]-=1 if(i[2]+i[1]-i[0])%i[1]==0 and i[2]!=i[0] and i[2]>=i[0]: print("YES\n") else: print("NO\n") ```
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Provide tags and a correct Python 3 solution for this coding contest problem. Ted has a pineapple. This pineapple is able to bark like a bulldog! At time t (in seconds) it barks for the first time. Then every s seconds after it, it barks twice with 1 second interval. Thus it barks at times t, t + s, t + s + 1, t + 2s, t + 2s + 1, etc. <image> Barney woke up in the morning and wants to eat the pineapple, but he can't eat it when it's barking. Barney plans to eat it at time x (in seconds), so he asked you to tell him if it's gonna bark at that time. Input The first and only line of input contains three integers t, s and x (0 ≤ t, x ≤ 109, 2 ≤ s ≤ 109) — the time the pineapple barks for the first time, the pineapple barking interval, and the time Barney wants to eat the pineapple respectively. Output Print a single "YES" (without quotes) if the pineapple will bark at time x or a single "NO" (without quotes) otherwise in the only line of output. Examples Input 3 10 4 Output NO Input 3 10 3 Output YES Input 3 8 51 Output YES Input 3 8 52 Output YES Note In the first and the second sample cases pineapple will bark at moments 3, 13, 14, ..., so it won't bark at the moment 4 and will bark at the moment 3. In the third and fourth sample cases pineapple will bark at moments 3, 11, 12, 19, 20, 27, 28, 35, 36, 43, 44, 51, 52, 59, ..., so it will bark at both moments 51 and 52. Tags: implementation, math Correct Solution: ``` t, s, x = [int(i) for i in input().split()] if x < t+s: if x == t: print("YES") else: print("NO") else: if (x-t)%s == 0 or (x-t)%s == 1: print("YES") else: print("NO") ```
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Provide tags and a correct Python 3 solution for this coding contest problem. Ted has a pineapple. This pineapple is able to bark like a bulldog! At time t (in seconds) it barks for the first time. Then every s seconds after it, it barks twice with 1 second interval. Thus it barks at times t, t + s, t + s + 1, t + 2s, t + 2s + 1, etc. <image> Barney woke up in the morning and wants to eat the pineapple, but he can't eat it when it's barking. Barney plans to eat it at time x (in seconds), so he asked you to tell him if it's gonna bark at that time. Input The first and only line of input contains three integers t, s and x (0 ≤ t, x ≤ 109, 2 ≤ s ≤ 109) — the time the pineapple barks for the first time, the pineapple barking interval, and the time Barney wants to eat the pineapple respectively. Output Print a single "YES" (without quotes) if the pineapple will bark at time x or a single "NO" (without quotes) otherwise in the only line of output. Examples Input 3 10 4 Output NO Input 3 10 3 Output YES Input 3 8 51 Output YES Input 3 8 52 Output YES Note In the first and the second sample cases pineapple will bark at moments 3, 13, 14, ..., so it won't bark at the moment 4 and will bark at the moment 3. In the third and fourth sample cases pineapple will bark at moments 3, 11, 12, 19, 20, 27, 28, 35, 36, 43, 44, 51, 52, 59, ..., so it will bark at both moments 51 and 52. Tags: implementation, math Correct Solution: ``` a=list(map(int,input().split())) if a[0]>a[2]: print("NO") else : if abs((a[2]-a[0]))%a[1]==1 and abs(a[2]-a[0])!=1 or abs((a[2]-a[0]))%a[1]==0 and abs(a[2]-a[0])!=1 : print('YES') else : print('NO') ```
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Provide tags and a correct Python 3 solution for this coding contest problem. Ted has a pineapple. This pineapple is able to bark like a bulldog! At time t (in seconds) it barks for the first time. Then every s seconds after it, it barks twice with 1 second interval. Thus it barks at times t, t + s, t + s + 1, t + 2s, t + 2s + 1, etc. <image> Barney woke up in the morning and wants to eat the pineapple, but he can't eat it when it's barking. Barney plans to eat it at time x (in seconds), so he asked you to tell him if it's gonna bark at that time. Input The first and only line of input contains three integers t, s and x (0 ≤ t, x ≤ 109, 2 ≤ s ≤ 109) — the time the pineapple barks for the first time, the pineapple barking interval, and the time Barney wants to eat the pineapple respectively. Output Print a single "YES" (without quotes) if the pineapple will bark at time x or a single "NO" (without quotes) otherwise in the only line of output. Examples Input 3 10 4 Output NO Input 3 10 3 Output YES Input 3 8 51 Output YES Input 3 8 52 Output YES Note In the first and the second sample cases pineapple will bark at moments 3, 13, 14, ..., so it won't bark at the moment 4 and will bark at the moment 3. In the third and fourth sample cases pineapple will bark at moments 3, 11, 12, 19, 20, 27, 28, 35, 36, 43, 44, 51, 52, 59, ..., so it will bark at both moments 51 and 52. Tags: implementation, math Correct Solution: ``` t, s, x = map(int, input().split()) print('YES' if x - t >= 0 and x - t != 1 and (x - t) % s <= 1 else 'NO') ```
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Provide tags and a correct Python 3 solution for this coding contest problem. Ted has a pineapple. This pineapple is able to bark like a bulldog! At time t (in seconds) it barks for the first time. Then every s seconds after it, it barks twice with 1 second interval. Thus it barks at times t, t + s, t + s + 1, t + 2s, t + 2s + 1, etc. <image> Barney woke up in the morning and wants to eat the pineapple, but he can't eat it when it's barking. Barney plans to eat it at time x (in seconds), so he asked you to tell him if it's gonna bark at that time. Input The first and only line of input contains three integers t, s and x (0 ≤ t, x ≤ 109, 2 ≤ s ≤ 109) — the time the pineapple barks for the first time, the pineapple barking interval, and the time Barney wants to eat the pineapple respectively. Output Print a single "YES" (without quotes) if the pineapple will bark at time x or a single "NO" (without quotes) otherwise in the only line of output. Examples Input 3 10 4 Output NO Input 3 10 3 Output YES Input 3 8 51 Output YES Input 3 8 52 Output YES Note In the first and the second sample cases pineapple will bark at moments 3, 13, 14, ..., so it won't bark at the moment 4 and will bark at the moment 3. In the third and fourth sample cases pineapple will bark at moments 3, 11, 12, 19, 20, 27, 28, 35, 36, 43, 44, 51, 52, 59, ..., so it will bark at both moments 51 and 52. Tags: implementation, math Correct Solution: ``` read = lambda: map(int, input().split()) t, s, x = read() f1 = (x - t) % s == 0 and x >= t f2 = (x - t - 1) % s == 0 and x > t + 1 print('YES' if (f1 or f2) else 'NO') ```
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Provide tags and a correct Python 3 solution for this coding contest problem. Ted has a pineapple. This pineapple is able to bark like a bulldog! At time t (in seconds) it barks for the first time. Then every s seconds after it, it barks twice with 1 second interval. Thus it barks at times t, t + s, t + s + 1, t + 2s, t + 2s + 1, etc. <image> Barney woke up in the morning and wants to eat the pineapple, but he can't eat it when it's barking. Barney plans to eat it at time x (in seconds), so he asked you to tell him if it's gonna bark at that time. Input The first and only line of input contains three integers t, s and x (0 ≤ t, x ≤ 109, 2 ≤ s ≤ 109) — the time the pineapple barks for the first time, the pineapple barking interval, and the time Barney wants to eat the pineapple respectively. Output Print a single "YES" (without quotes) if the pineapple will bark at time x or a single "NO" (without quotes) otherwise in the only line of output. Examples Input 3 10 4 Output NO Input 3 10 3 Output YES Input 3 8 51 Output YES Input 3 8 52 Output YES Note In the first and the second sample cases pineapple will bark at moments 3, 13, 14, ..., so it won't bark at the moment 4 and will bark at the moment 3. In the third and fourth sample cases pineapple will bark at moments 3, 11, 12, 19, 20, 27, 28, 35, 36, 43, 44, 51, 52, 59, ..., so it will bark at both moments 51 and 52. Tags: implementation, math Correct Solution: ``` # Description of the problem can be found at http://codeforces.com/problemset/problem/697/A t, s, x = map(int, input().split()) if t == x: print("YES") else: if (x - t) % s <= 1 and (x - t) // s > 0: print("YES") else: print("NO") ```
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Provide tags and a correct Python 3 solution for this coding contest problem. Ted has a pineapple. This pineapple is able to bark like a bulldog! At time t (in seconds) it barks for the first time. Then every s seconds after it, it barks twice with 1 second interval. Thus it barks at times t, t + s, t + s + 1, t + 2s, t + 2s + 1, etc. <image> Barney woke up in the morning and wants to eat the pineapple, but he can't eat it when it's barking. Barney plans to eat it at time x (in seconds), so he asked you to tell him if it's gonna bark at that time. Input The first and only line of input contains three integers t, s and x (0 ≤ t, x ≤ 109, 2 ≤ s ≤ 109) — the time the pineapple barks for the first time, the pineapple barking interval, and the time Barney wants to eat the pineapple respectively. Output Print a single "YES" (without quotes) if the pineapple will bark at time x or a single "NO" (without quotes) otherwise in the only line of output. Examples Input 3 10 4 Output NO Input 3 10 3 Output YES Input 3 8 51 Output YES Input 3 8 52 Output YES Note In the first and the second sample cases pineapple will bark at moments 3, 13, 14, ..., so it won't bark at the moment 4 and will bark at the moment 3. In the third and fourth sample cases pineapple will bark at moments 3, 11, 12, 19, 20, 27, 28, 35, 36, 43, 44, 51, 52, 59, ..., so it will bark at both moments 51 and 52. Tags: implementation, math Correct Solution: ``` a = input().split() t = int(a[0]) s = int(a[1]) x = int(a[2]) if (((x-t)%s!=0) and (((x-t)-1)%s!=0)) or (x-1==t) or x<t: print("NO") else: print("YES") ```
90,571
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Ted has a pineapple. This pineapple is able to bark like a bulldog! At time t (in seconds) it barks for the first time. Then every s seconds after it, it barks twice with 1 second interval. Thus it barks at times t, t + s, t + s + 1, t + 2s, t + 2s + 1, etc. <image> Barney woke up in the morning and wants to eat the pineapple, but he can't eat it when it's barking. Barney plans to eat it at time x (in seconds), so he asked you to tell him if it's gonna bark at that time. Input The first and only line of input contains three integers t, s and x (0 ≤ t, x ≤ 109, 2 ≤ s ≤ 109) — the time the pineapple barks for the first time, the pineapple barking interval, and the time Barney wants to eat the pineapple respectively. Output Print a single "YES" (without quotes) if the pineapple will bark at time x or a single "NO" (without quotes) otherwise in the only line of output. Examples Input 3 10 4 Output NO Input 3 10 3 Output YES Input 3 8 51 Output YES Input 3 8 52 Output YES Note In the first and the second sample cases pineapple will bark at moments 3, 13, 14, ..., so it won't bark at the moment 4 and will bark at the moment 3. In the third and fourth sample cases pineapple will bark at moments 3, 11, 12, 19, 20, 27, 28, 35, 36, 43, 44, 51, 52, 59, ..., so it will bark at both moments 51 and 52. Submitted Solution: ``` t,s,x=map(int,input().split()) if(x==t): print("YES") exit(0) else: if(x>t): if((x-t)%s==0 and (x-t)/s>=1): print("YES") exit(0) if((x-t-1)%s==0 and (x-t-1)/s>=1): print("YES") exit(0) print("NO") ``` Yes
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Ted has a pineapple. This pineapple is able to bark like a bulldog! At time t (in seconds) it barks for the first time. Then every s seconds after it, it barks twice with 1 second interval. Thus it barks at times t, t + s, t + s + 1, t + 2s, t + 2s + 1, etc. <image> Barney woke up in the morning and wants to eat the pineapple, but he can't eat it when it's barking. Barney plans to eat it at time x (in seconds), so he asked you to tell him if it's gonna bark at that time. Input The first and only line of input contains three integers t, s and x (0 ≤ t, x ≤ 109, 2 ≤ s ≤ 109) — the time the pineapple barks for the first time, the pineapple barking interval, and the time Barney wants to eat the pineapple respectively. Output Print a single "YES" (without quotes) if the pineapple will bark at time x or a single "NO" (without quotes) otherwise in the only line of output. Examples Input 3 10 4 Output NO Input 3 10 3 Output YES Input 3 8 51 Output YES Input 3 8 52 Output YES Note In the first and the second sample cases pineapple will bark at moments 3, 13, 14, ..., so it won't bark at the moment 4 and will bark at the moment 3. In the third and fourth sample cases pineapple will bark at moments 3, 11, 12, 19, 20, 27, 28, 35, 36, 43, 44, 51, 52, 59, ..., so it will bark at both moments 51 and 52. Submitted Solution: ``` [t,s,x]=[int(x) for x in input().split()] x-=t if (x%s==0 or x%s==1 and x!=1) and x>=0: print("YES") else: print("NO") ``` Yes
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Ted has a pineapple. This pineapple is able to bark like a bulldog! At time t (in seconds) it barks for the first time. Then every s seconds after it, it barks twice with 1 second interval. Thus it barks at times t, t + s, t + s + 1, t + 2s, t + 2s + 1, etc. <image> Barney woke up in the morning and wants to eat the pineapple, but he can't eat it when it's barking. Barney plans to eat it at time x (in seconds), so he asked you to tell him if it's gonna bark at that time. Input The first and only line of input contains three integers t, s and x (0 ≤ t, x ≤ 109, 2 ≤ s ≤ 109) — the time the pineapple barks for the first time, the pineapple barking interval, and the time Barney wants to eat the pineapple respectively. Output Print a single "YES" (without quotes) if the pineapple will bark at time x or a single "NO" (without quotes) otherwise in the only line of output. Examples Input 3 10 4 Output NO Input 3 10 3 Output YES Input 3 8 51 Output YES Input 3 8 52 Output YES Note In the first and the second sample cases pineapple will bark at moments 3, 13, 14, ..., so it won't bark at the moment 4 and will bark at the moment 3. In the third and fourth sample cases pineapple will bark at moments 3, 11, 12, 19, 20, 27, 28, 35, 36, 43, 44, 51, 52, 59, ..., so it will bark at both moments 51 and 52. Submitted Solution: ``` t,s,x=map(int,input().split()) print('NO'if(x<t)or(x-t)%s>>(x!=t+1)else'YES') ``` Yes
90,574
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Ted has a pineapple. This pineapple is able to bark like a bulldog! At time t (in seconds) it barks for the first time. Then every s seconds after it, it barks twice with 1 second interval. Thus it barks at times t, t + s, t + s + 1, t + 2s, t + 2s + 1, etc. <image> Barney woke up in the morning and wants to eat the pineapple, but he can't eat it when it's barking. Barney plans to eat it at time x (in seconds), so he asked you to tell him if it's gonna bark at that time. Input The first and only line of input contains three integers t, s and x (0 ≤ t, x ≤ 109, 2 ≤ s ≤ 109) — the time the pineapple barks for the first time, the pineapple barking interval, and the time Barney wants to eat the pineapple respectively. Output Print a single "YES" (without quotes) if the pineapple will bark at time x or a single "NO" (without quotes) otherwise in the only line of output. Examples Input 3 10 4 Output NO Input 3 10 3 Output YES Input 3 8 51 Output YES Input 3 8 52 Output YES Note In the first and the second sample cases pineapple will bark at moments 3, 13, 14, ..., so it won't bark at the moment 4 and will bark at the moment 3. In the third and fourth sample cases pineapple will bark at moments 3, 11, 12, 19, 20, 27, 28, 35, 36, 43, 44, 51, 52, 59, ..., so it will bark at both moments 51 and 52. Submitted Solution: ``` t,s,x = map(int, input().split(" ")) res = x-t if res < 0: print("NO") else: if res % s == 0 or ((res-1) % s) == 0: if res != 1: print("YES") else: print("NO") else: print("NO") ``` Yes
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Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Ted has a pineapple. This pineapple is able to bark like a bulldog! At time t (in seconds) it barks for the first time. Then every s seconds after it, it barks twice with 1 second interval. Thus it barks at times t, t + s, t + s + 1, t + 2s, t + 2s + 1, etc. <image> Barney woke up in the morning and wants to eat the pineapple, but he can't eat it when it's barking. Barney plans to eat it at time x (in seconds), so he asked you to tell him if it's gonna bark at that time. Input The first and only line of input contains three integers t, s and x (0 ≤ t, x ≤ 109, 2 ≤ s ≤ 109) — the time the pineapple barks for the first time, the pineapple barking interval, and the time Barney wants to eat the pineapple respectively. Output Print a single "YES" (without quotes) if the pineapple will bark at time x or a single "NO" (without quotes) otherwise in the only line of output. Examples Input 3 10 4 Output NO Input 3 10 3 Output YES Input 3 8 51 Output YES Input 3 8 52 Output YES Note In the first and the second sample cases pineapple will bark at moments 3, 13, 14, ..., so it won't bark at the moment 4 and will bark at the moment 3. In the third and fourth sample cases pineapple will bark at moments 3, 11, 12, 19, 20, 27, 28, 35, 36, 43, 44, 51, 52, 59, ..., so it will bark at both moments 51 and 52. Submitted Solution: ``` x,y,z=[int(a) for a in input().split()] if x==z: print("YES") xx=x while xx<z: xx+=xx+y if xx==z or xx+1==z: print("YES") quit() if xx==z or xx+1==z: print("YES") else: print("NO") ``` No
90,576
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Ted has a pineapple. This pineapple is able to bark like a bulldog! At time t (in seconds) it barks for the first time. Then every s seconds after it, it barks twice with 1 second interval. Thus it barks at times t, t + s, t + s + 1, t + 2s, t + 2s + 1, etc. <image> Barney woke up in the morning and wants to eat the pineapple, but he can't eat it when it's barking. Barney plans to eat it at time x (in seconds), so he asked you to tell him if it's gonna bark at that time. Input The first and only line of input contains three integers t, s and x (0 ≤ t, x ≤ 109, 2 ≤ s ≤ 109) — the time the pineapple barks for the first time, the pineapple barking interval, and the time Barney wants to eat the pineapple respectively. Output Print a single "YES" (without quotes) if the pineapple will bark at time x or a single "NO" (without quotes) otherwise in the only line of output. Examples Input 3 10 4 Output NO Input 3 10 3 Output YES Input 3 8 51 Output YES Input 3 8 52 Output YES Note In the first and the second sample cases pineapple will bark at moments 3, 13, 14, ..., so it won't bark at the moment 4 and will bark at the moment 3. In the third and fourth sample cases pineapple will bark at moments 3, 11, 12, 19, 20, 27, 28, 35, 36, 43, 44, 51, 52, 59, ..., so it will bark at both moments 51 and 52. Submitted Solution: ``` t, s, x = map(int, input().split()) if x < t: print('YES') else: if x == t + 1 and s != 1: print('NO') else: if (x - t) % s == 0 or (x - t - 1) % s == 0: print('YES') else: print('NO') ``` No
90,577
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Ted has a pineapple. This pineapple is able to bark like a bulldog! At time t (in seconds) it barks for the first time. Then every s seconds after it, it barks twice with 1 second interval. Thus it barks at times t, t + s, t + s + 1, t + 2s, t + 2s + 1, etc. <image> Barney woke up in the morning and wants to eat the pineapple, but he can't eat it when it's barking. Barney plans to eat it at time x (in seconds), so he asked you to tell him if it's gonna bark at that time. Input The first and only line of input contains three integers t, s and x (0 ≤ t, x ≤ 109, 2 ≤ s ≤ 109) — the time the pineapple barks for the first time, the pineapple barking interval, and the time Barney wants to eat the pineapple respectively. Output Print a single "YES" (without quotes) if the pineapple will bark at time x or a single "NO" (without quotes) otherwise in the only line of output. Examples Input 3 10 4 Output NO Input 3 10 3 Output YES Input 3 8 51 Output YES Input 3 8 52 Output YES Note In the first and the second sample cases pineapple will bark at moments 3, 13, 14, ..., so it won't bark at the moment 4 and will bark at the moment 3. In the third and fourth sample cases pineapple will bark at moments 3, 11, 12, 19, 20, 27, 28, 35, 36, 43, 44, 51, 52, 59, ..., so it will bark at both moments 51 and 52. Submitted Solution: ``` import sys container2=[] t,s,x= map(int, input().split()) a=(x-t)//s for i in range(a-10,a+10): if x == t+i*s or x==t+1+(i+1)*s: print('YES') elif t+1+(i+1)*s<x<t+i*s: print('NO') ``` No
90,578
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Ted has a pineapple. This pineapple is able to bark like a bulldog! At time t (in seconds) it barks for the first time. Then every s seconds after it, it barks twice with 1 second interval. Thus it barks at times t, t + s, t + s + 1, t + 2s, t + 2s + 1, etc. <image> Barney woke up in the morning and wants to eat the pineapple, but he can't eat it when it's barking. Barney plans to eat it at time x (in seconds), so he asked you to tell him if it's gonna bark at that time. Input The first and only line of input contains three integers t, s and x (0 ≤ t, x ≤ 109, 2 ≤ s ≤ 109) — the time the pineapple barks for the first time, the pineapple barking interval, and the time Barney wants to eat the pineapple respectively. Output Print a single "YES" (without quotes) if the pineapple will bark at time x or a single "NO" (without quotes) otherwise in the only line of output. Examples Input 3 10 4 Output NO Input 3 10 3 Output YES Input 3 8 51 Output YES Input 3 8 52 Output YES Note In the first and the second sample cases pineapple will bark at moments 3, 13, 14, ..., so it won't bark at the moment 4 and will bark at the moment 3. In the third and fourth sample cases pineapple will bark at moments 3, 11, 12, 19, 20, 27, 28, 35, 36, 43, 44, 51, 52, 59, ..., so it will bark at both moments 51 and 52. Submitted Solution: ``` t,s,x=map(int,input().split()) if t==x: print('YES') else: a=x//s if t+a*s==x or t+a*s+1==x and x>s: print('YES') else: print('NO') ``` No
90,579
Provide tags and a correct Python 3 solution for this coding contest problem. You are given two strings a and b. You have to remove the minimum possible number of consecutive (standing one after another) characters from string b in such a way that it becomes a subsequence of string a. It can happen that you will not need to remove any characters at all, or maybe you will have to remove all of the characters from b and make it empty. Subsequence of string s is any such string that can be obtained by erasing zero or more characters (not necessarily consecutive) from string s. Input The first line contains string a, and the second line — string b. Both of these strings are nonempty and consist of lowercase letters of English alphabet. The length of each string is no bigger than 105 characters. Output On the first line output a subsequence of string a, obtained from b by erasing the minimum number of consecutive characters. If the answer consists of zero characters, output «-» (a minus sign). Examples Input hi bob Output - Input abca accepted Output ac Input abacaba abcdcba Output abcba Note In the first example strings a and b don't share any symbols, so the longest string that you can get is empty. In the second example ac is a subsequence of a, and at the same time you can obtain it by erasing consecutive symbols cepted from string b. Tags: binary search, hashing, strings, two pointers Correct Solution: ``` a = list(input()) b = list(input()) s = [-1] i = 0 j = 0 while i < len(a) and j < len(b): if a[i] == b[j]: s.append(i) j += 1 i += 1 e = [10**6] i = len(a) - 1 j = len(b) - 1 while i >= 0 and j >= 0: if a[i] == b[j]: e.append(i) j -= 1 i -= 1 ans_len = 0 ans = ['-'] i = len(s) - 1 j = 0 while i >= 0 and j < len(e): if s[i] < e[j] and i + j - 1< len(b): new_len = j + i if new_len > ans_len: ans_len = new_len if j > 0: ans = b[:i] + b[-j:] else: ans = b[:i] j += 1 else: i -= 1 print(''.join(ans)) ```
90,580
Provide tags and a correct Python 3 solution for this coding contest problem. You are given two strings a and b. You have to remove the minimum possible number of consecutive (standing one after another) characters from string b in such a way that it becomes a subsequence of string a. It can happen that you will not need to remove any characters at all, or maybe you will have to remove all of the characters from b and make it empty. Subsequence of string s is any such string that can be obtained by erasing zero or more characters (not necessarily consecutive) from string s. Input The first line contains string a, and the second line — string b. Both of these strings are nonempty and consist of lowercase letters of English alphabet. The length of each string is no bigger than 105 characters. Output On the first line output a subsequence of string a, obtained from b by erasing the minimum number of consecutive characters. If the answer consists of zero characters, output «-» (a minus sign). Examples Input hi bob Output - Input abca accepted Output ac Input abacaba abcdcba Output abcba Note In the first example strings a and b don't share any symbols, so the longest string that you can get is empty. In the second example ac is a subsequence of a, and at the same time you can obtain it by erasing consecutive symbols cepted from string b. Tags: binary search, hashing, strings, two pointers Correct Solution: ``` import math def prefixIds(a, b): prefSubsId = [math.inf] * len(b) # print(a) # print(b) bId = 0 aId = 0 while aId < len(a): if bId == len(b): break if a[aId] == b[bId]: prefSubsId[bId] = aId + 1 bId += 1 aId += 1 else: aId += 1 return prefSubsId a = input() b = input() # print(a) # print(b) n = len(b) prefLens = prefixIds(a, b) suffLens = prefixIds(a[::-1], b[::-1])[::-1] # for i in range(n): # if suffLens[i] != math.inf: # suffLens[i] = len(a) - suffLens[i] # print(*prefLens, sep='\t') # print(*suffLens, sep='\t') prefLen = 0 suffLen = 0 minCutLen = n lBorder = -1 rBorder = n while suffLen < n and suffLens[suffLen] == math.inf: suffLen += 1 curCutLen = suffLen # print(curCutLen) if curCutLen < minCutLen: minCutLen = curCutLen rBorder = suffLen while prefLen < suffLen and prefLens[prefLen] != math.inf: while suffLen < n and prefLens[prefLen] + suffLens[suffLen] > len(a): # print(suffLen) suffLen += 1 # print(prefLen) # print(suffLen) curCutLen = suffLen - prefLen - 1 # print(curCutLen) if curCutLen < minCutLen: minCutLen = curCutLen lBorder = prefLen rBorder = suffLen prefLen += 1 # print(prefLens[prefLen]) # print(suffLens[suffLen]) # # print() # print("pref, suff") # print(prefLen) # print(suffLen) # print(minCutLen) # print(n) # print(lBorder) # print(rBorder) if minCutLen == n: print('-') elif minCutLen == 0: print(b) else: print(b[:lBorder + 1] + b[rBorder:]) # print(maxPrefLen) # print(maxSuffLen) ```
90,581
Provide tags and a correct Python 3 solution for this coding contest problem. You are given two strings a and b. You have to remove the minimum possible number of consecutive (standing one after another) characters from string b in such a way that it becomes a subsequence of string a. It can happen that you will not need to remove any characters at all, or maybe you will have to remove all of the characters from b and make it empty. Subsequence of string s is any such string that can be obtained by erasing zero or more characters (not necessarily consecutive) from string s. Input The first line contains string a, and the second line — string b. Both of these strings are nonempty and consist of lowercase letters of English alphabet. The length of each string is no bigger than 105 characters. Output On the first line output a subsequence of string a, obtained from b by erasing the minimum number of consecutive characters. If the answer consists of zero characters, output «-» (a minus sign). Examples Input hi bob Output - Input abca accepted Output ac Input abacaba abcdcba Output abcba Note In the first example strings a and b don't share any symbols, so the longest string that you can get is empty. In the second example ac is a subsequence of a, and at the same time you can obtain it by erasing consecutive symbols cepted from string b. Tags: binary search, hashing, strings, two pointers Correct Solution: ``` from sys import stdin def main(): t = stdin.readline() s = stdin.readline() n = len(s) - 1 m = len(t) - 1 post = [-1] * n ss = n - 1 st = m - 1 while st >= 0 and ss >= 0: if t[st] == s[ss]: post[ss] = st ss -= 1 st -= 1 pre = [-1] * n ss = 0 st = 0 while st < m and ss < n: if t[st] == s[ss]: pre[ss] = st ss += 1 st += 1 low = 0 high = n min_ans = n start = -1 end = -1 while low < high: mid = (low + high) >> 1 ok = False if post[mid] != -1: if mid < min_ans: min_ans = mid start = 0 end = mid - 1 ok = True for i in range(1, n - mid): if pre[i - 1] != -1 and post[i + mid] != -1 and post[i + mid] > pre[i - 1]: if mid < min_ans: min_ans = mid start = i end = i + mid - 1 ok = True if pre[n - mid - 1] != -1: if mid < min_ans: min_ans = mid start = n - mid end = n - 1 ok = True if not ok: low = mid + 1 else: high = mid ans = [] for i in range(n): if start <= i <= end: continue ans.append(s[i]) if min_ans == n: print('-') else: print(''.join(ans)) if __name__ == '__main__': main() ```
90,582
Provide tags and a correct Python 3 solution for this coding contest problem. You are given two strings a and b. You have to remove the minimum possible number of consecutive (standing one after another) characters from string b in such a way that it becomes a subsequence of string a. It can happen that you will not need to remove any characters at all, or maybe you will have to remove all of the characters from b and make it empty. Subsequence of string s is any such string that can be obtained by erasing zero or more characters (not necessarily consecutive) from string s. Input The first line contains string a, and the second line — string b. Both of these strings are nonempty and consist of lowercase letters of English alphabet. The length of each string is no bigger than 105 characters. Output On the first line output a subsequence of string a, obtained from b by erasing the minimum number of consecutive characters. If the answer consists of zero characters, output «-» (a minus sign). Examples Input hi bob Output - Input abca accepted Output ac Input abacaba abcdcba Output abcba Note In the first example strings a and b don't share any symbols, so the longest string that you can get is empty. In the second example ac is a subsequence of a, and at the same time you can obtain it by erasing consecutive symbols cepted from string b. Tags: binary search, hashing, strings, two pointers Correct Solution: ``` a = input() b = input() prefix = [-1] * len(b) postfix = [-1] * len(b) prefix[0] = a.find(b[0]) postfix[len(b) - 1] = a.rfind(b[len(b) - 1]) for i in range(1, len(b)): prefix[i] = a.find(b[i], prefix[i - 1] + 1) if prefix[i] == -1: break for i in range(len(b) - 2, -1, -1): postfix[i] = a.rfind(b[i], 0, postfix[i+1]) if postfix[i] == -1: break best_left = -1 best_right = len(b) left = -1 while left + 1 < len(b) and prefix[left + 1] != -1: left += 1 if left > -1: best_left = left best_right = len(b) right = len(b) while right - 1 >= 0 and postfix[right - 1] != -1: right -= 1 if right < len(b) and right + 1 < best_right - best_left: best_left = -1 best_right = right left = 0 right = len(b) while left < right and postfix[right - 1] != -1 and postfix[right - 1] > prefix[left]: right -= 1 while prefix[left] != -1 and left < right < len(b): while right < len(b) and postfix[right] <= prefix[left]: right += 1 if right >= len(b): break if right - left < best_right - best_left: best_left = left best_right = right left += 1 if left == right: right += 1 res = b[:best_left + 1] + b[best_right:] if res == "": print("-") else: print(res) ```
90,583
Provide tags and a correct Python 3 solution for this coding contest problem. You are given two strings a and b. You have to remove the minimum possible number of consecutive (standing one after another) characters from string b in such a way that it becomes a subsequence of string a. It can happen that you will not need to remove any characters at all, or maybe you will have to remove all of the characters from b and make it empty. Subsequence of string s is any such string that can be obtained by erasing zero or more characters (not necessarily consecutive) from string s. Input The first line contains string a, and the second line — string b. Both of these strings are nonempty and consist of lowercase letters of English alphabet. The length of each string is no bigger than 105 characters. Output On the first line output a subsequence of string a, obtained from b by erasing the minimum number of consecutive characters. If the answer consists of zero characters, output «-» (a minus sign). Examples Input hi bob Output - Input abca accepted Output ac Input abacaba abcdcba Output abcba Note In the first example strings a and b don't share any symbols, so the longest string that you can get is empty. In the second example ac is a subsequence of a, and at the same time you can obtain it by erasing consecutive symbols cepted from string b. Tags: binary search, hashing, strings, two pointers Correct Solution: ``` import sys s, t = input(), '*'+input() n, m = len(s), len(t)-1 inf = 10**9 pre, suf = [-1] + [inf]*(m+1), [-1]*(m+1) + [n] i = 0 for j in range(1, m+1): while i < n and s[i] != t[j]: i += 1 if i == n: break pre[j] = i i += 1 i = n-1 for j in range(m, 0, -1): while 0 <= i and s[i] != t[j]: i -= 1 if i == -1: break suf[j] = i i -= 1 max_len, best_l, best_r = 0, 0, 0 j = 1 for i in range(m+1): j = max(j, i+1) while j <= m and pre[i] >= suf[j]: j += 1 if pre[i] == inf: break if max_len < i + m + 1 - j: max_len = i + m + 1 - j best_l, best_r = i, j pre_s = t[1:best_l+1] suf_s = t[best_r:] print(pre_s + suf_s if max_len else '-') ```
90,584
Provide tags and a correct Python 3 solution for this coding contest problem. You are given two strings a and b. You have to remove the minimum possible number of consecutive (standing one after another) characters from string b in such a way that it becomes a subsequence of string a. It can happen that you will not need to remove any characters at all, or maybe you will have to remove all of the characters from b and make it empty. Subsequence of string s is any such string that can be obtained by erasing zero or more characters (not necessarily consecutive) from string s. Input The first line contains string a, and the second line — string b. Both of these strings are nonempty and consist of lowercase letters of English alphabet. The length of each string is no bigger than 105 characters. Output On the first line output a subsequence of string a, obtained from b by erasing the minimum number of consecutive characters. If the answer consists of zero characters, output «-» (a minus sign). Examples Input hi bob Output - Input abca accepted Output ac Input abacaba abcdcba Output abcba Note In the first example strings a and b don't share any symbols, so the longest string that you can get is empty. In the second example ac is a subsequence of a, and at the same time you can obtain it by erasing consecutive symbols cepted from string b. Tags: binary search, hashing, strings, two pointers Correct Solution: ``` import sys input = sys.stdin.readline def solve(): a = input().strip() b = input().strip() n = len(a) m = len(b) c = [0]*m d = [0]*m p = 0 for i in range(m): for j in range(p, n): if a[j] == b[i]: c[i] = j p = j + 1 break else: for j in range(i,m): c[j] = n break p = n-1 for i in range(m-1,-1,-1): for j in range(p,-1,-1): if a[j] == b[i]: d[i] = j p = j - 1 break else: for j in range(i,-1,-1): d[j] = -1 break j = 0 while j < m and d[j] < 0: j += 1 res = (m-j, 0, j) for i in range(m): p = c[i] if p == n: break while j < m and (j <= i or d[j] <= p): j += 1 res = max(res,(i+1+m-j,i+1,j)) if res[0] == 0: print('-') else: print(b[:res[1]]+b[res[2]:]) solve() ```
90,585
Provide tags and a correct Python 3 solution for this coding contest problem. You are given two strings a and b. You have to remove the minimum possible number of consecutive (standing one after another) characters from string b in such a way that it becomes a subsequence of string a. It can happen that you will not need to remove any characters at all, or maybe you will have to remove all of the characters from b and make it empty. Subsequence of string s is any such string that can be obtained by erasing zero or more characters (not necessarily consecutive) from string s. Input The first line contains string a, and the second line — string b. Both of these strings are nonempty and consist of lowercase letters of English alphabet. The length of each string is no bigger than 105 characters. Output On the first line output a subsequence of string a, obtained from b by erasing the minimum number of consecutive characters. If the answer consists of zero characters, output «-» (a minus sign). Examples Input hi bob Output - Input abca accepted Output ac Input abacaba abcdcba Output abcba Note In the first example strings a and b don't share any symbols, so the longest string that you can get is empty. In the second example ac is a subsequence of a, and at the same time you can obtain it by erasing consecutive symbols cepted from string b. Tags: binary search, hashing, strings, two pointers Correct Solution: ``` a, b = str(input()), str(input()) p, s, pp, sp = [0] * len(b), [0] * len(b), 0, len(a) - 1 p[0] = a.find(b[0]) while sp >= 0 and a[sp] != b[-1]: sp -= 1 s[len(b) - 1] = sp pp, sp = p[0] + 1, sp - 1 for i in range(1, len(b)): if p[i - 1] == -1: p[i] = -1 else: while pp < len(a) and a[pp] != b[i]: pp += 1 p[i] = (pp if pp < len(a) else -1) pp += 1 for i in range(len(b) - 2, -1, -1): if s[i + 1] == -1: s[i] = -1 else: while sp >= 0 and a[sp] != b[i]: sp -= 1 s[i] = (sp if sp >= 0 else -1) sp -= 1 anss, ans = 0, (-1, -1, -1) for i in range(0, len(b)): if p[i] == -1: break while anss < len(b) and (s[anss] <= p[i] or s[anss] == -1) or anss <= i: anss += 1 ln = (i + 1 if p[i] != -1 else 0) + (len(b) - anss if anss < len(b) and s[anss] != -1 else 0) if ln > ans[0]: ans = (ln, i, anss) only_s = len(b) - 1 while only_s - 1 >= 0 and s[only_s - 1] >= 0: only_s -= 1 if only_s >= 0 and s[-1] >= 0 and len(b) - only_s > ans[0]: print(b[only_s:]) elif ans[0] == -1: print("-") else: print(b[:ans[1] + 1] + (b[ans[2]:] if ans[2] < len(b) else "")) ```
90,586
Provide tags and a correct Python 3 solution for this coding contest problem. You are given two strings a and b. You have to remove the minimum possible number of consecutive (standing one after another) characters from string b in such a way that it becomes a subsequence of string a. It can happen that you will not need to remove any characters at all, or maybe you will have to remove all of the characters from b and make it empty. Subsequence of string s is any such string that can be obtained by erasing zero or more characters (not necessarily consecutive) from string s. Input The first line contains string a, and the second line — string b. Both of these strings are nonempty and consist of lowercase letters of English alphabet. The length of each string is no bigger than 105 characters. Output On the first line output a subsequence of string a, obtained from b by erasing the minimum number of consecutive characters. If the answer consists of zero characters, output «-» (a minus sign). Examples Input hi bob Output - Input abca accepted Output ac Input abacaba abcdcba Output abcba Note In the first example strings a and b don't share any symbols, so the longest string that you can get is empty. In the second example ac is a subsequence of a, and at the same time you can obtain it by erasing consecutive symbols cepted from string b. Tags: binary search, hashing, strings, two pointers Correct Solution: ``` a=input() b=input() pre=[len(a) for i in range(len(b))] suf=[-1 for i in range(len(b))] temp=0 whole=0 for i in range(len(a)): if b[temp]==a[i]: pre[temp]=i temp+=1 if temp==len(b): whole=1 break temp=len(b)-1 for i in range(len(a)-1,-1,-1): if b[temp]==a[i]: suf[temp]=i temp-=1 if temp==-1: whole=1 break ans=[] index=0 for i in range(len(b)): temp=pre[i] index=max(i+1,index) start=index for j in range(start,len(b)): if suf[j]>pre[i]: index=j break else: index=len(b) if index!=len(b) and pre[i]!=len(a): ans+=[len(b)+1+i-index] elif pre[i]==len(a): ans+=[0] elif index==len(b) and pre[i]!=len(a): ans+=[i+1] else: ans+=[0] MAXsufANS=0 MAXsufindex=len(b) for i in range(len(b)-1,-1,-1): if suf[i]!=-1: MAXsufANS=len(b)-i MAXsufindex=i MAX=0 MAXindex=-1 for i in range(len(b)): if ans[i]>MAX: MAXindex=i MAX=ans[i] usesuf=0 if MAXsufANS>MAX: usesuf=1 if whole==1: print(b) else: if max(MAX,MAXsufANS)==0: print('-') else: if usesuf==1: anss=b[MAXsufindex:] print(anss) else: m=MAXindex L=MAX anss=b[:m+1]+b[len(b)-(MAX-(m+1)):] print(anss) ```
90,587
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given two strings a and b. You have to remove the minimum possible number of consecutive (standing one after another) characters from string b in such a way that it becomes a subsequence of string a. It can happen that you will not need to remove any characters at all, or maybe you will have to remove all of the characters from b and make it empty. Subsequence of string s is any such string that can be obtained by erasing zero or more characters (not necessarily consecutive) from string s. Input The first line contains string a, and the second line — string b. Both of these strings are nonempty and consist of lowercase letters of English alphabet. The length of each string is no bigger than 105 characters. Output On the first line output a subsequence of string a, obtained from b by erasing the minimum number of consecutive characters. If the answer consists of zero characters, output «-» (a minus sign). Examples Input hi bob Output - Input abca accepted Output ac Input abacaba abcdcba Output abcba Note In the first example strings a and b don't share any symbols, so the longest string that you can get is empty. In the second example ac is a subsequence of a, and at the same time you can obtain it by erasing consecutive symbols cepted from string b. Submitted Solution: ``` #import sys #sys.stdin = open('in', 'r') #n = int(input()) #a = [int(x) for x in input().split()] #n,m = map(int, input().split()) s1 = input() s2 = input() l1 = len(s1) l2 = len(s2) dl = {} dr = {} i1 = 0 i2 = 0 while i1 < l1 and i2 < l2: while i1 < l1 and s1[i1] != s2[i2]: i1 += 1 if i1 < l1: dl[i2] = i1 i2 += 1 i1 += 1 lmax = i2 if lmax == l2: print(s2) else: i1 = l1 - 1 i2 = l2 - 1 while i1 >= 0 and i2 >= 0: while i1 >= 0 and s1[i1] != s2[i2]: i1 -= 1 if i1 >= 0: dr[i2] = i1 i2 -= 1 i1 -= 1 rmax = i2 le = -1 re = -1 if l2 - lmax < rmax + 1: rcnt = l2 - lmax ls = 0 rs = lmax else: rcnt = rmax + 1 ls = rmax + 1 rs = l2 rr = rmax + 1 for ll in range(lmax): while rr < l2 and (rr <= ll or dl[ll] >= dr[rr]): rr += 1 if rr < l2: dif = rr - ll - 1 if dif < rcnt: rcnt = dif ls = 0 rs = ll + 1 le = rr re = l2 result = s2[ls:rs] if le != -1: result += s2[le:re] print(result if len(result) > 0 else '-') ``` Yes
90,588
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given two strings a and b. You have to remove the minimum possible number of consecutive (standing one after another) characters from string b in such a way that it becomes a subsequence of string a. It can happen that you will not need to remove any characters at all, or maybe you will have to remove all of the characters from b and make it empty. Subsequence of string s is any such string that can be obtained by erasing zero or more characters (not necessarily consecutive) from string s. Input The first line contains string a, and the second line — string b. Both of these strings are nonempty and consist of lowercase letters of English alphabet. The length of each string is no bigger than 105 characters. Output On the first line output a subsequence of string a, obtained from b by erasing the minimum number of consecutive characters. If the answer consists of zero characters, output «-» (a minus sign). Examples Input hi bob Output - Input abca accepted Output ac Input abacaba abcdcba Output abcba Note In the first example strings a and b don't share any symbols, so the longest string that you can get is empty. In the second example ac is a subsequence of a, and at the same time you can obtain it by erasing consecutive symbols cepted from string b. Submitted Solution: ``` from macpath import curdir import bisect a=input() b=input() la=len(a) lb=len(b) forb=[la]*lb cur=0 for i in range(lb): while cur<la and a[cur]!=b[i]: cur+=1 if cur<la: forb[i]=cur cur+=1 else: break cur=la-1 bacb=[-1]*lb for i in range(lb-1,-1,-1): while cur>=0 and a[cur]!=b[i]: cur-=1 if cur>=0: bacb[i]=cur cur-=1 else: break res=lb start=0 end=lb for i in range(lb): low=-1 if i>0 : low=forb[i-1] if low>=la: break j=bisect.bisect_right(bacb,low) if res>j-i>=0: res=j-i start=i end=j if res==lb: print('-') else: print(b[:start]+b[end:]) ``` Yes
90,589
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given two strings a and b. You have to remove the minimum possible number of consecutive (standing one after another) characters from string b in such a way that it becomes a subsequence of string a. It can happen that you will not need to remove any characters at all, or maybe you will have to remove all of the characters from b and make it empty. Subsequence of string s is any such string that can be obtained by erasing zero or more characters (not necessarily consecutive) from string s. Input The first line contains string a, and the second line — string b. Both of these strings are nonempty and consist of lowercase letters of English alphabet. The length of each string is no bigger than 105 characters. Output On the first line output a subsequence of string a, obtained from b by erasing the minimum number of consecutive characters. If the answer consists of zero characters, output «-» (a minus sign). Examples Input hi bob Output - Input abca accepted Output ac Input abacaba abcdcba Output abcba Note In the first example strings a and b don't share any symbols, so the longest string that you can get is empty. In the second example ac is a subsequence of a, and at the same time you can obtain it by erasing consecutive symbols cepted from string b. Submitted Solution: ``` # cook your dish here a = list(input()) b = list(input()) m = len(a) n = len(b) s = [-1] i = 0 j = 0 while i<m and j<n: if(a[i]==b[j]): s.append(i) j+=1 i+=1 e = [1000000] i = m-1 j= n-1 while i>=0 and j>=0: if(a[i]==b[j]): e.append(i) j-=1 i-=1 i = len(s)-1 j = 0 ans = "-" ctr = 0 while j<len(e) and i>=0: if(s[i]<e[j]): if(i+j > ctr and i+j<=len(b)): ctr = i+j if(j>0): ans = b[:i] + b[-j:] else: ans = b[:i] j+=1 else: i -= 1 print(''.join(ans)) ``` Yes
90,590
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given two strings a and b. You have to remove the minimum possible number of consecutive (standing one after another) characters from string b in such a way that it becomes a subsequence of string a. It can happen that you will not need to remove any characters at all, or maybe you will have to remove all of the characters from b and make it empty. Subsequence of string s is any such string that can be obtained by erasing zero or more characters (not necessarily consecutive) from string s. Input The first line contains string a, and the second line — string b. Both of these strings are nonempty and consist of lowercase letters of English alphabet. The length of each string is no bigger than 105 characters. Output On the first line output a subsequence of string a, obtained from b by erasing the minimum number of consecutive characters. If the answer consists of zero characters, output «-» (a minus sign). Examples Input hi bob Output - Input abca accepted Output ac Input abacaba abcdcba Output abcba Note In the first example strings a and b don't share any symbols, so the longest string that you can get is empty. In the second example ac is a subsequence of a, and at the same time you can obtain it by erasing consecutive symbols cepted from string b. Submitted Solution: ``` a = input() b = input() p = [None] * (len(b) + 1) s = [None] * (len(b) + 1) j = 0 p[0] = -1 for i in range(len(b)): while j < len(a) and a[j] != b[i]: j += 1 if j >= len(a): break else: p[i + 1] = j j += 1 j = len(a) - 1 s[-1] = len(b) for i in range(len(b) - 1, -1, -1): while j >= 0 and a[j] != b[i]: j -= 1 if j < 0: break else: s[i] = j j -= 1 ans = "" for i in range(len(b) + 1): if p[i] == None: break else: l = i - 1 r = len(b) while l + 1 < r: mid = (l + r) // 2 if s[mid] != None and p[i] < s[mid]: r = mid else: l = mid if len(ans) < i + len(b) - r: ans = b[:i] + b[r:] if ans == "": print("-") else: print(ans) ``` Yes
90,591
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given two strings a and b. You have to remove the minimum possible number of consecutive (standing one after another) characters from string b in such a way that it becomes a subsequence of string a. It can happen that you will not need to remove any characters at all, or maybe you will have to remove all of the characters from b and make it empty. Subsequence of string s is any such string that can be obtained by erasing zero or more characters (not necessarily consecutive) from string s. Input The first line contains string a, and the second line — string b. Both of these strings are nonempty and consist of lowercase letters of English alphabet. The length of each string is no bigger than 105 characters. Output On the first line output a subsequence of string a, obtained from b by erasing the minimum number of consecutive characters. If the answer consists of zero characters, output «-» (a minus sign). Examples Input hi bob Output - Input abca accepted Output ac Input abacaba abcdcba Output abcba Note In the first example strings a and b don't share any symbols, so the longest string that you can get is empty. In the second example ac is a subsequence of a, and at the same time you can obtain it by erasing consecutive symbols cepted from string b. Submitted Solution: ``` import sys s = list(map(lambda c: ord(c)-97, input())) t = list(map(lambda c: ord(c)-97, input())) n, m = len(s), len(t) next_c = [[-1]*26 for _ in range(n+1)] for i in range(n-1, -1, -1): for j in range(26): next_c[i][j] = next_c[i+1][j] next_c[i][s[i]] = i+1 minf = -(10**9) dp = [[minf, minf, minf] for _ in range(m+1)] dp_i = [[0, 0, 0] for _ in range(m+1)] dp[0][0] = 0 def solve1(i1, j1, i2, j2, c): next_i = next_c[dp_i[i2][j2]][c] if next_i != -1 and (dp[i1][j1] < dp[i2][j2]+1 or dp[i1][j1] == dp[i2][j2]+1 and dp_i[i1][j1] > next_i): dp[i1][j1] = dp[i2][j2]+1 dp_i[i1][j1] = next_i def solve2(i1, j1, i2, j2): if dp[i1][j1] < dp[i2][j2] or dp[i1][j1] == dp[i2][j2] and dp_i[i1][j1] > dp_i[i2][j2]: dp[i1][j1] = dp[i2][j2] dp_i[i1][j1] = dp_i[i2][j2] for i in range(m): solve1(i+1, 0, i, 0, t[i]) solve2(i+1, 1, i, 0) solve2(i+1, 1, i, 1) solve1(i+1, 2, i, 1, t[i]) solve1(i+1, 2, i, 2, t[i]) i, j, max_len = 0, 0, 0 for jj in range(3): if max_len < dp[m][jj]: i, j, max_len = m, jj, dp[m][jj] ans = [] while i > 0: if j == 1 and dp[i-1][j] == dp[i][j] and dp_i[i-1][j] == dp_i[i][j]: i -= 1 continue if j == 1 and dp[i-1][j-1] == dp[i][j] and dp_i[i-1][j-1] == dp_i[i][j]: i -= 1 j -= 1 continue if j != 1 and dp[i-1][j]+1 == dp[i][j] and dp_i[i-1][j] < dp_i[i][j]: ans.append(chr(97 + t[i-1])) i -= 1 continue if j == 2 and dp[i-1][j-1]+1 == dp[i][j] and dp_i[i-1][j-1] < dp_i[i][j]: ans.append(chr(97 + t[i-1])) i -= 1 j -= 1 print(''.join(reversed(ans)) if ans else '-') ``` No
90,592
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given two strings a and b. You have to remove the minimum possible number of consecutive (standing one after another) characters from string b in such a way that it becomes a subsequence of string a. It can happen that you will not need to remove any characters at all, or maybe you will have to remove all of the characters from b and make it empty. Subsequence of string s is any such string that can be obtained by erasing zero or more characters (not necessarily consecutive) from string s. Input The first line contains string a, and the second line — string b. Both of these strings are nonempty and consist of lowercase letters of English alphabet. The length of each string is no bigger than 105 characters. Output On the first line output a subsequence of string a, obtained from b by erasing the minimum number of consecutive characters. If the answer consists of zero characters, output «-» (a minus sign). Examples Input hi bob Output - Input abca accepted Output ac Input abacaba abcdcba Output abcba Note In the first example strings a and b don't share any symbols, so the longest string that you can get is empty. In the second example ac is a subsequence of a, and at the same time you can obtain it by erasing consecutive symbols cepted from string b. Submitted Solution: ``` a=input() b=input() aa=list(a) bb=list(b) cc=[] for i in range(len(aa)): for j in range(len(bb)): if aa[i]==bb[j]: cc.append(aa[i]) bb.pop(j) break if len(cc)==0: print('-') else: for i in range(len(b)): for j in range(len(cc)): if b[i]==cc[j]: print(b[i],end='') cc.pop(j) break ``` No
90,593
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given two strings a and b. You have to remove the minimum possible number of consecutive (standing one after another) characters from string b in such a way that it becomes a subsequence of string a. It can happen that you will not need to remove any characters at all, or maybe you will have to remove all of the characters from b and make it empty. Subsequence of string s is any such string that can be obtained by erasing zero or more characters (not necessarily consecutive) from string s. Input The first line contains string a, and the second line — string b. Both of these strings are nonempty and consist of lowercase letters of English alphabet. The length of each string is no bigger than 105 characters. Output On the first line output a subsequence of string a, obtained from b by erasing the minimum number of consecutive characters. If the answer consists of zero characters, output «-» (a minus sign). Examples Input hi bob Output - Input abca accepted Output ac Input abacaba abcdcba Output abcba Note In the first example strings a and b don't share any symbols, so the longest string that you can get is empty. In the second example ac is a subsequence of a, and at the same time you can obtain it by erasing consecutive symbols cepted from string b. Submitted Solution: ``` a=str(input()) b=str(input()) counter=0 i=0 j=0 while i<len(b): if(a[j]!=b[i] ): k=j while True: if(k>len(a)-1): break if(a[k]==b[i]): break k+=1 if(k==len(a)): newstr = b.replace(b[i], "") b=newstr counter+=1 i+=1 j+=1 if(not(j<len(a))): break if(counter==len(a)-1): print("_") else: print(b) ``` No
90,594
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. You are given two strings a and b. You have to remove the minimum possible number of consecutive (standing one after another) characters from string b in such a way that it becomes a subsequence of string a. It can happen that you will not need to remove any characters at all, or maybe you will have to remove all of the characters from b and make it empty. Subsequence of string s is any such string that can be obtained by erasing zero or more characters (not necessarily consecutive) from string s. Input The first line contains string a, and the second line — string b. Both of these strings are nonempty and consist of lowercase letters of English alphabet. The length of each string is no bigger than 105 characters. Output On the first line output a subsequence of string a, obtained from b by erasing the minimum number of consecutive characters. If the answer consists of zero characters, output «-» (a minus sign). Examples Input hi bob Output - Input abca accepted Output ac Input abacaba abcdcba Output abcba Note In the first example strings a and b don't share any symbols, so the longest string that you can get is empty. In the second example ac is a subsequence of a, and at the same time you can obtain it by erasing consecutive symbols cepted from string b. Submitted Solution: ``` import sys s = list(map(lambda c: ord(c)-97, input())) t = list(map(lambda c: ord(c)-97, input())) n, m = len(s), len(t) i = n-1 ans1 = [] for j in range(m-1, -1, -1): while 0 <= i and s[i] != t[j]: i -= 1 if i < 0: break ans1.append(chr(97 + t[j])) i -= 1 next_c = [[-1]*26 for _ in range(n+1)] for i in range(n-1, -1, -1): for j in range(26): next_c[i][j] = next_c[i+1][j] next_c[i][s[i]] = i+1 minf = -(10**9) dp = [[minf, 0, minf] for _ in range(m+1)] dp_i = [[0, 0, 0] for _ in range(m+1)] dp[0][0] = 0 prev = [[(0, 0, 0), (0, 0, 0), (0, 0, 0)] for _ in range(m+1)] def solve1(i1, j1, i2, j2, c): next_i = next_c[dp_i[i2][j2]][c] if next_i != -1 and (dp[i1][j1] < dp[i2][j2]+1 or dp[i1][j1] == dp[i2][j2]+1 and dp_i[i1][j1] > next_i): dp[i1][j1] = dp[i2][j2]+1 dp_i[i1][j1] = next_i prev[i1][j1] = (i2, j2, 1) def solve2(i1, j1, i2, j2): if dp[i1][j1] < dp[i2][j2] or dp[i1][j1] == dp[i2][j2] and dp_i[i1][j1] > dp_i[i2][j2]: dp[i1][j1] = dp[i2][j2] dp_i[i1][j1] = dp_i[i2][j2] prev[i1][j1] = (i2, j2, 0) for i in range(m): solve1(i+1, 0, i, 0, t[i]) solve2(i+1, 1, i, 0) solve2(i+1, 1, i, 1) solve1(i+1, 2, i, 1, t[i]) solve1(i+1, 2, i, 2, t[i]) i, j, max_len = 0, 0, 0 for jj in range(3): if max_len < dp[m][jj]: i, j, max_len = m, jj, dp[m][jj] ans = [] while i > 0: i, j, flag = prev[i][j] if flag: ans.append(chr(97 + t[i])) if len(ans1) > len(ans): ans = ''.join(reversed(ans1)) else: ans = ''.join(reversed(ans)) print(ans if ans else '-') ``` No
90,595
Provide tags and a correct Python 3 solution for this coding contest problem. As you probably know, Anton goes to school. One of the school subjects that Anton studies is Bracketology. On the Bracketology lessons students usually learn different sequences that consist of round brackets (characters "(" and ")" (without quotes)). On the last lesson Anton learned about the regular simple bracket sequences (RSBS). A bracket sequence s of length n is an RSBS if the following conditions are met: * It is not empty (that is n ≠ 0). * The length of the sequence is even. * First <image> charactes of the sequence are equal to "(". * Last <image> charactes of the sequence are equal to ")". For example, the sequence "((()))" is an RSBS but the sequences "((())" and "(()())" are not RSBS. Elena Ivanovna, Anton's teacher, gave him the following task as a homework. Given a bracket sequence s. Find the number of its distinct subsequences such that they are RSBS. Note that a subsequence of s is a string that can be obtained from s by deleting some of its elements. Two subsequences are considered distinct if distinct sets of positions are deleted. Because the answer can be very big and Anton's teacher doesn't like big numbers, she asks Anton to find the answer modulo 109 + 7. Anton thought of this task for a very long time, but he still doesn't know how to solve it. Help Anton to solve this task and write a program that finds the answer for it! Input The only line of the input contains a string s — the bracket sequence given in Anton's homework. The string consists only of characters "(" and ")" (without quotes). It's guaranteed that the string is not empty and its length doesn't exceed 200 000. Output Output one number — the answer for the task modulo 109 + 7. Examples Input )(()() Output 6 Input ()()() Output 7 Input ))) Output 0 Note In the first sample the following subsequences are possible: * If we delete characters at the positions 1 and 5 (numbering starts with one), we will get the subsequence "(())". * If we delete characters at the positions 1, 2, 3 and 4, we will get the subsequence "()". * If we delete characters at the positions 1, 2, 4 and 5, we will get the subsequence "()". * If we delete characters at the positions 1, 2, 5 and 6, we will get the subsequence "()". * If we delete characters at the positions 1, 3, 4 and 5, we will get the subsequence "()". * If we delete characters at the positions 1, 3, 5 and 6, we will get the subsequence "()". The rest of the subsequnces are not RSBS. So we got 6 distinct subsequences that are RSBS, so the answer is 6. Tags: combinatorics, dp, math, number theory Correct Solution: ``` t = input() n, m = len(t) + 1, 1000000007 a, b = 0, t.count(')') - 1 f = [1] * n for i in range(2, n): f[i] = i * f[i - 1] % m g = [pow(q, m - 2, m) for q in f] s = 0 for q in t: if b < 0: break if q == '(': a += 1 s += f[a + b] * g[a] * g[b] else: b -= 1 print(s % m) ```
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Provide tags and a correct Python 3 solution for this coding contest problem. As you probably know, Anton goes to school. One of the school subjects that Anton studies is Bracketology. On the Bracketology lessons students usually learn different sequences that consist of round brackets (characters "(" and ")" (without quotes)). On the last lesson Anton learned about the regular simple bracket sequences (RSBS). A bracket sequence s of length n is an RSBS if the following conditions are met: * It is not empty (that is n ≠ 0). * The length of the sequence is even. * First <image> charactes of the sequence are equal to "(". * Last <image> charactes of the sequence are equal to ")". For example, the sequence "((()))" is an RSBS but the sequences "((())" and "(()())" are not RSBS. Elena Ivanovna, Anton's teacher, gave him the following task as a homework. Given a bracket sequence s. Find the number of its distinct subsequences such that they are RSBS. Note that a subsequence of s is a string that can be obtained from s by deleting some of its elements. Two subsequences are considered distinct if distinct sets of positions are deleted. Because the answer can be very big and Anton's teacher doesn't like big numbers, she asks Anton to find the answer modulo 109 + 7. Anton thought of this task for a very long time, but he still doesn't know how to solve it. Help Anton to solve this task and write a program that finds the answer for it! Input The only line of the input contains a string s — the bracket sequence given in Anton's homework. The string consists only of characters "(" and ")" (without quotes). It's guaranteed that the string is not empty and its length doesn't exceed 200 000. Output Output one number — the answer for the task modulo 109 + 7. Examples Input )(()() Output 6 Input ()()() Output 7 Input ))) Output 0 Note In the first sample the following subsequences are possible: * If we delete characters at the positions 1 and 5 (numbering starts with one), we will get the subsequence "(())". * If we delete characters at the positions 1, 2, 3 and 4, we will get the subsequence "()". * If we delete characters at the positions 1, 2, 4 and 5, we will get the subsequence "()". * If we delete characters at the positions 1, 2, 5 and 6, we will get the subsequence "()". * If we delete characters at the positions 1, 3, 4 and 5, we will get the subsequence "()". * If we delete characters at the positions 1, 3, 5 and 6, we will get the subsequence "()". The rest of the subsequnces are not RSBS. So we got 6 distinct subsequences that are RSBS, so the answer is 6. Tags: combinatorics, dp, math, number theory Correct Solution: ``` mod = 10 ** 9 + 7 s = input() n = len(s) f = [1] * (n + 1) for i in range(1, n + 1): f[i] = i * f[i - 1] % mod finv = [pow(x, mod - 2, mod) for x in f] op = 0 cl = s.count(')') ans = 0 if cl > 0: for c in s: if c == '(': op += 1 ans += f[op + cl - 1] * finv[cl - 1] * finv[op] elif cl <= 1: break else: cl -= 1 print(ans % mod) ```
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Provide tags and a correct Python 3 solution for this coding contest problem. As you probably know, Anton goes to school. One of the school subjects that Anton studies is Bracketology. On the Bracketology lessons students usually learn different sequences that consist of round brackets (characters "(" and ")" (without quotes)). On the last lesson Anton learned about the regular simple bracket sequences (RSBS). A bracket sequence s of length n is an RSBS if the following conditions are met: * It is not empty (that is n ≠ 0). * The length of the sequence is even. * First <image> charactes of the sequence are equal to "(". * Last <image> charactes of the sequence are equal to ")". For example, the sequence "((()))" is an RSBS but the sequences "((())" and "(()())" are not RSBS. Elena Ivanovna, Anton's teacher, gave him the following task as a homework. Given a bracket sequence s. Find the number of its distinct subsequences such that they are RSBS. Note that a subsequence of s is a string that can be obtained from s by deleting some of its elements. Two subsequences are considered distinct if distinct sets of positions are deleted. Because the answer can be very big and Anton's teacher doesn't like big numbers, she asks Anton to find the answer modulo 109 + 7. Anton thought of this task for a very long time, but he still doesn't know how to solve it. Help Anton to solve this task and write a program that finds the answer for it! Input The only line of the input contains a string s — the bracket sequence given in Anton's homework. The string consists only of characters "(" and ")" (without quotes). It's guaranteed that the string is not empty and its length doesn't exceed 200 000. Output Output one number — the answer for the task modulo 109 + 7. Examples Input )(()() Output 6 Input ()()() Output 7 Input ))) Output 0 Note In the first sample the following subsequences are possible: * If we delete characters at the positions 1 and 5 (numbering starts with one), we will get the subsequence "(())". * If we delete characters at the positions 1, 2, 3 and 4, we will get the subsequence "()". * If we delete characters at the positions 1, 2, 4 and 5, we will get the subsequence "()". * If we delete characters at the positions 1, 2, 5 and 6, we will get the subsequence "()". * If we delete characters at the positions 1, 3, 4 and 5, we will get the subsequence "()". * If we delete characters at the positions 1, 3, 5 and 6, we will get the subsequence "()". The rest of the subsequnces are not RSBS. So we got 6 distinct subsequences that are RSBS, so the answer is 6. Tags: combinatorics, dp, math, number theory Correct Solution: ``` mod = 10 ** 9 + 7 fact, inv, invfact = [1, 1], [0, 1], [1, 1] for i in range(2, 200200): fact.append(fact[-1] * i % mod) inv.append(inv[mod % i] * (mod - mod // i) % mod) invfact.append(invfact[-1] * inv[-1] % mod) def C(n, k): if k < 0 or k > n: return 0 return fact[n] * invfact[k] * invfact[n - k] % mod s = input() op, cl = 0, s.count(')') ans = 0 for x in s: if x == '(': op += 1 cur = C(cl + op - 1, op) ans += cur else: cl -= 1 print(ans % mod) ```
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Provide tags and a correct Python 3 solution for this coding contest problem. As you probably know, Anton goes to school. One of the school subjects that Anton studies is Bracketology. On the Bracketology lessons students usually learn different sequences that consist of round brackets (characters "(" and ")" (without quotes)). On the last lesson Anton learned about the regular simple bracket sequences (RSBS). A bracket sequence s of length n is an RSBS if the following conditions are met: * It is not empty (that is n ≠ 0). * The length of the sequence is even. * First <image> charactes of the sequence are equal to "(". * Last <image> charactes of the sequence are equal to ")". For example, the sequence "((()))" is an RSBS but the sequences "((())" and "(()())" are not RSBS. Elena Ivanovna, Anton's teacher, gave him the following task as a homework. Given a bracket sequence s. Find the number of its distinct subsequences such that they are RSBS. Note that a subsequence of s is a string that can be obtained from s by deleting some of its elements. Two subsequences are considered distinct if distinct sets of positions are deleted. Because the answer can be very big and Anton's teacher doesn't like big numbers, she asks Anton to find the answer modulo 109 + 7. Anton thought of this task for a very long time, but he still doesn't know how to solve it. Help Anton to solve this task and write a program that finds the answer for it! Input The only line of the input contains a string s — the bracket sequence given in Anton's homework. The string consists only of characters "(" and ")" (without quotes). It's guaranteed that the string is not empty and its length doesn't exceed 200 000. Output Output one number — the answer for the task modulo 109 + 7. Examples Input )(()() Output 6 Input ()()() Output 7 Input ))) Output 0 Note In the first sample the following subsequences are possible: * If we delete characters at the positions 1 and 5 (numbering starts with one), we will get the subsequence "(())". * If we delete characters at the positions 1, 2, 3 and 4, we will get the subsequence "()". * If we delete characters at the positions 1, 2, 4 and 5, we will get the subsequence "()". * If we delete characters at the positions 1, 2, 5 and 6, we will get the subsequence "()". * If we delete characters at the positions 1, 3, 4 and 5, we will get the subsequence "()". * If we delete characters at the positions 1, 3, 5 and 6, we will get the subsequence "()". The rest of the subsequnces are not RSBS. So we got 6 distinct subsequences that are RSBS, so the answer is 6. Tags: combinatorics, dp, math, number theory Correct Solution: ``` #!/usr/bin/env python3 def ri(): return map(int, input().split()) m = 10**9+7 s = input() n = len(s) o = [0 for i in range(len(s))] c = [0 for i in range(len(s))] fac = [0 for i in range(n)] fac[0] = 1 for i in range(1,n): fac[i] = fac[i-1]*i%m invfac = [pow(fac[i], m-2, m) for i in range(n)] if s[0] == '(': o[0] = 1 for i in range(1,n): if s[i] == '(': o[i] = o[i-1] + 1 else: o[i] = o[i-1] if s[n-1] == ')': c[n-1] = 1 for i in range(n-2, -1, -1): if s[i] == ')': c[i] = c[i+1] + 1 else: c[i] = c[i+1] ans = 0 for i in range(n): if s[i] == '(': a = o[i] b = c[i] if a != 0 and b != 0: ans += fac[a+b-1]*invfac[a]*invfac[b-1] ans %= m print(ans) ```
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