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Provide tags and a correct Python 3 solution for this coding contest problem. A company has n employees numbered from 1 to n. Each employee either has no immediate manager or exactly one immediate manager, who is another employee with a different number. An employee A is said to be the superior of another employee B if at least one of the following is true: * Employee A is the immediate manager of employee B * Employee B has an immediate manager employee C such that employee A is the superior of employee C. The company will not have a managerial cycle. That is, there will not exist an employee who is the superior of his/her own immediate manager. Today the company is going to arrange a party. This involves dividing all n employees into several groups: every employee must belong to exactly one group. Furthermore, within any single group, there must not be two employees A and B such that A is the superior of B. What is the minimum number of groups that must be formed? Input The first line contains integer n (1 ≀ n ≀ 2000) β€” the number of employees. The next n lines contain the integers pi (1 ≀ pi ≀ n or pi = -1). Every pi denotes the immediate manager for the i-th employee. If pi is -1, that means that the i-th employee does not have an immediate manager. It is guaranteed, that no employee will be the immediate manager of him/herself (pi β‰  i). Also, there will be no managerial cycles. Output Print a single integer denoting the minimum number of groups that will be formed in the party. Examples Input 5 -1 1 2 1 -1 Output 3 Note For the first example, three groups are sufficient, for example: * Employee 1 * Employees 2 and 4 * Employees 3 and 5
instruction
0
1,715
14
3,430
Tags: dfs and similar, graphs, trees Correct Solution: ``` from collections import deque def bfs(u): global n, al, dist, prev, used q = deque() q.append(u) md = 1 used[u] = True while len(q) > 0: v = q.popleft() for i in al[v]: if not used[i]: used[i] = True dist[i] = dist[v] + 1 if dist[i] + 1 > md: md = dist[i] + 1 q.append(i) return md n = int(input()) al = [[] for i in range(n)] dist = [0] * n prev = [0] * n used = [False] * n p = [-1] * n for i in range(n): x = int(input()) - 1 if x >= 0: p[i] = x al[x].append(i) res = 0 a = [] for i in range(n): if p[i] == -1: a.append(i) i = 0 while i < len(a): if not used[a[i]]: res = max(res, bfs(a[i])) else: i += 1 print(res) ```
output
1
1,715
14
3,431
Provide tags and a correct Python 3 solution for this coding contest problem. A company has n employees numbered from 1 to n. Each employee either has no immediate manager or exactly one immediate manager, who is another employee with a different number. An employee A is said to be the superior of another employee B if at least one of the following is true: * Employee A is the immediate manager of employee B * Employee B has an immediate manager employee C such that employee A is the superior of employee C. The company will not have a managerial cycle. That is, there will not exist an employee who is the superior of his/her own immediate manager. Today the company is going to arrange a party. This involves dividing all n employees into several groups: every employee must belong to exactly one group. Furthermore, within any single group, there must not be two employees A and B such that A is the superior of B. What is the minimum number of groups that must be formed? Input The first line contains integer n (1 ≀ n ≀ 2000) β€” the number of employees. The next n lines contain the integers pi (1 ≀ pi ≀ n or pi = -1). Every pi denotes the immediate manager for the i-th employee. If pi is -1, that means that the i-th employee does not have an immediate manager. It is guaranteed, that no employee will be the immediate manager of him/herself (pi β‰  i). Also, there will be no managerial cycles. Output Print a single integer denoting the minimum number of groups that will be formed in the party. Examples Input 5 -1 1 2 1 -1 Output 3 Note For the first example, three groups are sufficient, for example: * Employee 1 * Employees 2 and 4 * Employees 3 and 5
instruction
0
1,716
14
3,432
Tags: dfs and similar, graphs, trees Correct Solution: ``` def findDepth(a, i): depth = 1 nextLevel = a[i][:] while len(nextLevel) > 0: depth += 1 children = nextLevel[:] nextLevel = [] for child in children: nextLevel += a[child] return depth n = int(input()) a = [] for i in range(n): a.append([]) roots = [] for i in range(n): x = int(input()) if x > 0: a[x-1].append(i) else: roots.append(i) print(max([findDepth(a, i) for i in roots])) ```
output
1
1,716
14
3,433
Provide tags and a correct Python 3 solution for this coding contest problem. A company has n employees numbered from 1 to n. Each employee either has no immediate manager or exactly one immediate manager, who is another employee with a different number. An employee A is said to be the superior of another employee B if at least one of the following is true: * Employee A is the immediate manager of employee B * Employee B has an immediate manager employee C such that employee A is the superior of employee C. The company will not have a managerial cycle. That is, there will not exist an employee who is the superior of his/her own immediate manager. Today the company is going to arrange a party. This involves dividing all n employees into several groups: every employee must belong to exactly one group. Furthermore, within any single group, there must not be two employees A and B such that A is the superior of B. What is the minimum number of groups that must be formed? Input The first line contains integer n (1 ≀ n ≀ 2000) β€” the number of employees. The next n lines contain the integers pi (1 ≀ pi ≀ n or pi = -1). Every pi denotes the immediate manager for the i-th employee. If pi is -1, that means that the i-th employee does not have an immediate manager. It is guaranteed, that no employee will be the immediate manager of him/herself (pi β‰  i). Also, there will be no managerial cycles. Output Print a single integer denoting the minimum number of groups that will be formed in the party. Examples Input 5 -1 1 2 1 -1 Output 3 Note For the first example, three groups are sufficient, for example: * Employee 1 * Employees 2 and 4 * Employees 3 and 5
instruction
0
1,717
14
3,434
Tags: dfs and similar, graphs, trees Correct Solution: ``` n=int(input()) p=[int(input())-1 for i in range(n)] m=0 for i in range(len(p)): c=0 while i!=-2: c+=1 i=p[i] m=max(c,m) print(m) # Made By Mostafa_Khaled ```
output
1
1,717
14
3,435
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. A company has n employees numbered from 1 to n. Each employee either has no immediate manager or exactly one immediate manager, who is another employee with a different number. An employee A is said to be the superior of another employee B if at least one of the following is true: * Employee A is the immediate manager of employee B * Employee B has an immediate manager employee C such that employee A is the superior of employee C. The company will not have a managerial cycle. That is, there will not exist an employee who is the superior of his/her own immediate manager. Today the company is going to arrange a party. This involves dividing all n employees into several groups: every employee must belong to exactly one group. Furthermore, within any single group, there must not be two employees A and B such that A is the superior of B. What is the minimum number of groups that must be formed? Input The first line contains integer n (1 ≀ n ≀ 2000) β€” the number of employees. The next n lines contain the integers pi (1 ≀ pi ≀ n or pi = -1). Every pi denotes the immediate manager for the i-th employee. If pi is -1, that means that the i-th employee does not have an immediate manager. It is guaranteed, that no employee will be the immediate manager of him/herself (pi β‰  i). Also, there will be no managerial cycles. Output Print a single integer denoting the minimum number of groups that will be formed in the party. Examples Input 5 -1 1 2 1 -1 Output 3 Note For the first example, three groups are sufficient, for example: * Employee 1 * Employees 2 and 4 * Employees 3 and 5 Submitted Solution: ``` from sys import setrecursionlimit setrecursionlimit(30000) maxl = -1 def dfs(v, lvl): used[v] = True global maxl if lvl > maxl: maxl = lvl for u in ch[v]: dfs(u, lvl + 1) n = int(input()) used = [False] * n p = [int(input()) - 1 for i in range(n)] ch = [[] for i in range(n)] for i in range(n): if p[i] != -2: ch[p[i]].append(i) for i in range(n): if p[i] == -2: dfs(i, 1) print(maxl) ```
instruction
0
1,718
14
3,436
Yes
output
1
1,718
14
3,437
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. A company has n employees numbered from 1 to n. Each employee either has no immediate manager or exactly one immediate manager, who is another employee with a different number. An employee A is said to be the superior of another employee B if at least one of the following is true: * Employee A is the immediate manager of employee B * Employee B has an immediate manager employee C such that employee A is the superior of employee C. The company will not have a managerial cycle. That is, there will not exist an employee who is the superior of his/her own immediate manager. Today the company is going to arrange a party. This involves dividing all n employees into several groups: every employee must belong to exactly one group. Furthermore, within any single group, there must not be two employees A and B such that A is the superior of B. What is the minimum number of groups that must be formed? Input The first line contains integer n (1 ≀ n ≀ 2000) β€” the number of employees. The next n lines contain the integers pi (1 ≀ pi ≀ n or pi = -1). Every pi denotes the immediate manager for the i-th employee. If pi is -1, that means that the i-th employee does not have an immediate manager. It is guaranteed, that no employee will be the immediate manager of him/herself (pi β‰  i). Also, there will be no managerial cycles. Output Print a single integer denoting the minimum number of groups that will be formed in the party. Examples Input 5 -1 1 2 1 -1 Output 3 Note For the first example, three groups are sufficient, for example: * Employee 1 * Employees 2 and 4 * Employees 3 and 5 Submitted Solution: ``` from collections import * class graph: # initialize graph def __init__(self, gdict=None): if gdict is None: gdict = defaultdict(list) self.gdict, self.edges = gdict, [] # Get verticies def get_vertices(self): return list(self.gdict.keys()) # add edge def add_edge(self, node1, node2): self.gdict[node1].append(node2) # self.gdict[node2].append(node1) self.edges.append([node1, node2]) def bfs_util(self, i): queue, self.visit[i], level = deque([[i, 1]]), 1, 1 while queue: # dequeue parent vertix s, level = queue.popleft() # enqueue child vertices for i in self.gdict[s]: if self.visit[i] == 0: queue.append([i, level + 1]) self.visit[i] = 1 return level def bfs(self): self.visit, self.cnt = defaultdict(int), 0 for i in pars: if self.visit[i] == 0: self.cnt = max(self.bfs_util(i), self.cnt) return self.cnt n, g, pars = int(input()), graph(), [] for i in range(1, n + 1): x = int(input()) if x == -1: pars.append(i) else: g.add_edge(x, i) print(g.bfs()) ```
instruction
0
1,719
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3,438
Yes
output
1
1,719
14
3,439
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. A company has n employees numbered from 1 to n. Each employee either has no immediate manager or exactly one immediate manager, who is another employee with a different number. An employee A is said to be the superior of another employee B if at least one of the following is true: * Employee A is the immediate manager of employee B * Employee B has an immediate manager employee C such that employee A is the superior of employee C. The company will not have a managerial cycle. That is, there will not exist an employee who is the superior of his/her own immediate manager. Today the company is going to arrange a party. This involves dividing all n employees into several groups: every employee must belong to exactly one group. Furthermore, within any single group, there must not be two employees A and B such that A is the superior of B. What is the minimum number of groups that must be formed? Input The first line contains integer n (1 ≀ n ≀ 2000) β€” the number of employees. The next n lines contain the integers pi (1 ≀ pi ≀ n or pi = -1). Every pi denotes the immediate manager for the i-th employee. If pi is -1, that means that the i-th employee does not have an immediate manager. It is guaranteed, that no employee will be the immediate manager of him/herself (pi β‰  i). Also, there will be no managerial cycles. Output Print a single integer denoting the minimum number of groups that will be formed in the party. Examples Input 5 -1 1 2 1 -1 Output 3 Note For the first example, three groups are sufficient, for example: * Employee 1 * Employees 2 and 4 * Employees 3 and 5 Submitted Solution: ``` inp,m = [int(input())-1 for n in range(int(input()))],0 for i in range(len(inp)): c = 0 while i != -2: c+=1; i = inp[i] m = max(c,m) print(m) ```
instruction
0
1,720
14
3,440
Yes
output
1
1,720
14
3,441
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. A company has n employees numbered from 1 to n. Each employee either has no immediate manager or exactly one immediate manager, who is another employee with a different number. An employee A is said to be the superior of another employee B if at least one of the following is true: * Employee A is the immediate manager of employee B * Employee B has an immediate manager employee C such that employee A is the superior of employee C. The company will not have a managerial cycle. That is, there will not exist an employee who is the superior of his/her own immediate manager. Today the company is going to arrange a party. This involves dividing all n employees into several groups: every employee must belong to exactly one group. Furthermore, within any single group, there must not be two employees A and B such that A is the superior of B. What is the minimum number of groups that must be formed? Input The first line contains integer n (1 ≀ n ≀ 2000) β€” the number of employees. The next n lines contain the integers pi (1 ≀ pi ≀ n or pi = -1). Every pi denotes the immediate manager for the i-th employee. If pi is -1, that means that the i-th employee does not have an immediate manager. It is guaranteed, that no employee will be the immediate manager of him/herself (pi β‰  i). Also, there will be no managerial cycles. Output Print a single integer denoting the minimum number of groups that will be formed in the party. Examples Input 5 -1 1 2 1 -1 Output 3 Note For the first example, three groups are sufficient, for example: * Employee 1 * Employees 2 and 4 * Employees 3 and 5 Submitted Solution: ``` # Hint: Find the longest chain of command. size =int(input()) lis = [-1]*(size) for y in range(size): lis[y] = int(input()) - 1 r = [0]*(size) for x in range(size): c = x while lis[c] >-1: # Adding the employee to the manager r[x] += 1 # Moving up the chain c = lis[c] print (max(r)+1) ```
instruction
0
1,721
14
3,442
Yes
output
1
1,721
14
3,443
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. A company has n employees numbered from 1 to n. Each employee either has no immediate manager or exactly one immediate manager, who is another employee with a different number. An employee A is said to be the superior of another employee B if at least one of the following is true: * Employee A is the immediate manager of employee B * Employee B has an immediate manager employee C such that employee A is the superior of employee C. The company will not have a managerial cycle. That is, there will not exist an employee who is the superior of his/her own immediate manager. Today the company is going to arrange a party. This involves dividing all n employees into several groups: every employee must belong to exactly one group. Furthermore, within any single group, there must not be two employees A and B such that A is the superior of B. What is the minimum number of groups that must be formed? Input The first line contains integer n (1 ≀ n ≀ 2000) β€” the number of employees. The next n lines contain the integers pi (1 ≀ pi ≀ n or pi = -1). Every pi denotes the immediate manager for the i-th employee. If pi is -1, that means that the i-th employee does not have an immediate manager. It is guaranteed, that no employee will be the immediate manager of him/herself (pi β‰  i). Also, there will be no managerial cycles. Output Print a single integer denoting the minimum number of groups that will be formed in the party. Examples Input 5 -1 1 2 1 -1 Output 3 Note For the first example, three groups are sufficient, for example: * Employee 1 * Employees 2 and 4 * Employees 3 and 5 Submitted Solution: ``` from collections import deque def bfs(u): global n, al, dist, prev, used q = deque() q.append(u) md = 1 used[u] = True while len(q) > 0: v = q.popleft() for i in al[v]: if not used[i]: used[i] = True dist[i] = dist[v] + 1 if dist[i] + 1 > md: md = dist[i] + 1 q.append(i) return md n = int(input()) al = [[] for i in range(n)] dist = [0] * n prev = [0] * n used = [False] * n for i in range(n): x = int(input()) - 1 if x >= 0: al[x].append(i) res = 0 for i in range(n): if not used[i]: res = max(res, bfs(i)) print(res) ```
instruction
0
1,722
14
3,444
No
output
1
1,722
14
3,445
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. A company has n employees numbered from 1 to n. Each employee either has no immediate manager or exactly one immediate manager, who is another employee with a different number. An employee A is said to be the superior of another employee B if at least one of the following is true: * Employee A is the immediate manager of employee B * Employee B has an immediate manager employee C such that employee A is the superior of employee C. The company will not have a managerial cycle. That is, there will not exist an employee who is the superior of his/her own immediate manager. Today the company is going to arrange a party. This involves dividing all n employees into several groups: every employee must belong to exactly one group. Furthermore, within any single group, there must not be two employees A and B such that A is the superior of B. What is the minimum number of groups that must be formed? Input The first line contains integer n (1 ≀ n ≀ 2000) β€” the number of employees. The next n lines contain the integers pi (1 ≀ pi ≀ n or pi = -1). Every pi denotes the immediate manager for the i-th employee. If pi is -1, that means that the i-th employee does not have an immediate manager. It is guaranteed, that no employee will be the immediate manager of him/herself (pi β‰  i). Also, there will be no managerial cycles. Output Print a single integer denoting the minimum number of groups that will be formed in the party. Examples Input 5 -1 1 2 1 -1 Output 3 Note For the first example, three groups are sufficient, for example: * Employee 1 * Employees 2 and 4 * Employees 3 and 5 Submitted Solution: ``` n=int(input()) a=[] for i in range(n+1): a.append([]) for i in range(1,n+1): p=int(input()) if p!=-1: a[p].append(i) ans=1 for b in a: if len(b)>0: ans=2 for x in b: if len(a[x])>0: print(3) exit() print(ans) ```
instruction
0
1,723
14
3,446
No
output
1
1,723
14
3,447
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. A company has n employees numbered from 1 to n. Each employee either has no immediate manager or exactly one immediate manager, who is another employee with a different number. An employee A is said to be the superior of another employee B if at least one of the following is true: * Employee A is the immediate manager of employee B * Employee B has an immediate manager employee C such that employee A is the superior of employee C. The company will not have a managerial cycle. That is, there will not exist an employee who is the superior of his/her own immediate manager. Today the company is going to arrange a party. This involves dividing all n employees into several groups: every employee must belong to exactly one group. Furthermore, within any single group, there must not be two employees A and B such that A is the superior of B. What is the minimum number of groups that must be formed? Input The first line contains integer n (1 ≀ n ≀ 2000) β€” the number of employees. The next n lines contain the integers pi (1 ≀ pi ≀ n or pi = -1). Every pi denotes the immediate manager for the i-th employee. If pi is -1, that means that the i-th employee does not have an immediate manager. It is guaranteed, that no employee will be the immediate manager of him/herself (pi β‰  i). Also, there will be no managerial cycles. Output Print a single integer denoting the minimum number of groups that will be formed in the party. Examples Input 5 -1 1 2 1 -1 Output 3 Note For the first example, three groups are sufficient, for example: * Employee 1 * Employees 2 and 4 * Employees 3 and 5 Submitted Solution: ``` #------------------------template--------------------------# import os import sys from math import * from collections import * from bisect import * from io import BytesIO, IOBase def vsInput(): sys.stdin = open('input.txt', 'r') sys.stdout = open('output.txt', 'w') 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") def value(): return map(int,input().split()) def array(): return [int(i) for i in input().split()] #-------------------------code---------------------------# #vsInput() def bfs(adj,s,n,vis): vis[s]=True qu=[s] c=0 while(len(qu)!=0): e=qu.pop(0) flag=0 for i in adj[e]: if(vis[i]!=True): flag=1 qu.append(i) vis[i]=True if(flag==1): c+=1 return c+1 adj=defaultdict(list) n=int(input()) for i in range(n): a=int(input()) if(a!=-1): adj[a].append(i+1) else: adj[i+1]=[] #print(adj) ans=0 vis={i:False for i in range(1,n+1)} for i in range(1,n+1): if(vis[i]==False): ans=max(ans,bfs(adj,i,n,vis)) #print(bfs(adj,i,n,vis),i) print(ans) ```
instruction
0
1,724
14
3,448
No
output
1
1,724
14
3,449
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. A company has n employees numbered from 1 to n. Each employee either has no immediate manager or exactly one immediate manager, who is another employee with a different number. An employee A is said to be the superior of another employee B if at least one of the following is true: * Employee A is the immediate manager of employee B * Employee B has an immediate manager employee C such that employee A is the superior of employee C. The company will not have a managerial cycle. That is, there will not exist an employee who is the superior of his/her own immediate manager. Today the company is going to arrange a party. This involves dividing all n employees into several groups: every employee must belong to exactly one group. Furthermore, within any single group, there must not be two employees A and B such that A is the superior of B. What is the minimum number of groups that must be formed? Input The first line contains integer n (1 ≀ n ≀ 2000) β€” the number of employees. The next n lines contain the integers pi (1 ≀ pi ≀ n or pi = -1). Every pi denotes the immediate manager for the i-th employee. If pi is -1, that means that the i-th employee does not have an immediate manager. It is guaranteed, that no employee will be the immediate manager of him/herself (pi β‰  i). Also, there will be no managerial cycles. Output Print a single integer denoting the minimum number of groups that will be formed in the party. Examples Input 5 -1 1 2 1 -1 Output 3 Note For the first example, three groups are sufficient, for example: * Employee 1 * Employees 2 and 4 * Employees 3 and 5 Submitted Solution: ``` n=int(input()) a=[] for i in range(n+1): a.append([]) for i in range(1,n+1): p=int(input()) if p!=-1: a[p].append(i) print(a) ans=1 for b in a: if len(b)>0: ans=2 for x in b: if len(a[x])>0: print(3) exit() print(ans) ```
instruction
0
1,725
14
3,450
No
output
1
1,725
14
3,451
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Ivan is a programming teacher. During the academic year, he plans to give n lectures on n different topics. Each topic should be used in exactly one lecture. Ivan wants to choose which topic will he explain during the 1-st, 2-nd, ..., n-th lecture β€” formally, he wants to choose some permutation of integers from 1 to n (let's call this permutation q). q_i is the index of the topic Ivan will explain during the i-th lecture. For each topic (except exactly one), there exists a prerequisite topic (for the topic i, the prerequisite topic is p_i). Ivan cannot give a lecture on a topic before giving a lecture on its prerequisite topic. There exists at least one valid ordering of topics according to these prerequisite constraints. Ordering the topics correctly can help students understand the lectures better. Ivan has k special pairs of topics (x_i, y_i) such that he knows that the students will understand the y_i-th topic better if the lecture on it is conducted right after the lecture on the x_i-th topic. Ivan wants to satisfy the constraints on every such pair, that is, for every i ∈ [1, k], there should exist some j ∈ [1, n - 1] such that q_j = x_i and q_{j + 1} = y_i. Now Ivan wants to know if there exists an ordering of topics that satisfies all these constraints, and if at least one exists, find any of them. Input The first line contains two integers n and k (2 ≀ n ≀ 3 β‹… 10^5, 1 ≀ k ≀ n - 1) β€” the number of topics and the number of special pairs of topics, respectively. The second line contains n integers p_1, p_2, ..., p_n (0 ≀ p_i ≀ n), where p_i is the prerequisite topic for the topic i (or p_i = 0 if the i-th topic has no prerequisite topics). Exactly one of these integers is 0. At least one ordering of topics such that for every i the p_i-th topic is placed before the i-th topic exists. Then k lines follow, the i-th line contains two integers x_i and y_i (1 ≀ x_i, y_i ≀ n; x_i β‰  y_i) β€” the topics from the i-th special pair. All values of x_i are pairwise distinct; similarly, all valus of y_i are pairwise distinct. Output If there is no ordering of topics meeting all the constraints, print 0. Otherwise, print n pairwise distinct integers q_1, q_2, ..., q_n (1 ≀ q_i ≀ n) β€” the ordering of topics meeting all of the constraints. If there are multiple answers, print any of them. Examples Input 5 2 2 3 0 5 3 1 5 5 4 Output 3 2 1 5 4 Input 5 2 2 3 0 5 3 1 5 5 1 Output 0 Input 5 1 2 3 0 5 3 4 5 Output 0 Input 5 4 2 3 0 5 3 2 1 3 5 5 2 1 4 Output 3 5 2 1 4 Submitted Solution: ``` def main(): n,k = map(int, input().split());pp = [int(a)-1 for a in input().split()];chainhead = [True]*n;follower = [None]*n for _ in range(k): x, y = map(int, input().split()) if follower[x-1]:print(0);return else:follower[x-1] = y-1;chainhead[y-1] = False chain = list(range(n));cd = [0]*n for i in range(n): if chainhead[i]: f = follower[i];d = 1 while f != None:cd[f] = d;d += 1;chain[f] = i;f = follower[f] chainparents = [[] for _ in range(n)];ccount = [0]*n for i in range(n): if pp[i] != -1: if chain[i] != chain[pp[i]]:chainparents[chain[i]].append(chain[pp[i]]);ccount[chain[pp[i]]] += 1 elif cd[pp[i]] > cd[i]:print(0);return s = [i for i in range(n) if chainhead[i] and ccount[i] == 0];l = [];res = [] while s: v = s.pop();l.append(v) for p in chainparents[v]: ccount[p] -= 1 if ccount[p] == 0:s.append(p) if any(ccount[i] != 0 for i in range(n)):print(0);return for h in l[::-1]: c = h while c != None:res.append(c+1);c = follower[c] print(' '.join(map(str, res))) main() ```
instruction
0
1,861
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3,722
Yes
output
1
1,861
14
3,723
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Ivan is a programming teacher. During the academic year, he plans to give n lectures on n different topics. Each topic should be used in exactly one lecture. Ivan wants to choose which topic will he explain during the 1-st, 2-nd, ..., n-th lecture β€” formally, he wants to choose some permutation of integers from 1 to n (let's call this permutation q). q_i is the index of the topic Ivan will explain during the i-th lecture. For each topic (except exactly one), there exists a prerequisite topic (for the topic i, the prerequisite topic is p_i). Ivan cannot give a lecture on a topic before giving a lecture on its prerequisite topic. There exists at least one valid ordering of topics according to these prerequisite constraints. Ordering the topics correctly can help students understand the lectures better. Ivan has k special pairs of topics (x_i, y_i) such that he knows that the students will understand the y_i-th topic better if the lecture on it is conducted right after the lecture on the x_i-th topic. Ivan wants to satisfy the constraints on every such pair, that is, for every i ∈ [1, k], there should exist some j ∈ [1, n - 1] such that q_j = x_i and q_{j + 1} = y_i. Now Ivan wants to know if there exists an ordering of topics that satisfies all these constraints, and if at least one exists, find any of them. Input The first line contains two integers n and k (2 ≀ n ≀ 3 β‹… 10^5, 1 ≀ k ≀ n - 1) β€” the number of topics and the number of special pairs of topics, respectively. The second line contains n integers p_1, p_2, ..., p_n (0 ≀ p_i ≀ n), where p_i is the prerequisite topic for the topic i (or p_i = 0 if the i-th topic has no prerequisite topics). Exactly one of these integers is 0. At least one ordering of topics such that for every i the p_i-th topic is placed before the i-th topic exists. Then k lines follow, the i-th line contains two integers x_i and y_i (1 ≀ x_i, y_i ≀ n; x_i β‰  y_i) β€” the topics from the i-th special pair. All values of x_i are pairwise distinct; similarly, all valus of y_i are pairwise distinct. Output If there is no ordering of topics meeting all the constraints, print 0. Otherwise, print n pairwise distinct integers q_1, q_2, ..., q_n (1 ≀ q_i ≀ n) β€” the ordering of topics meeting all of the constraints. If there are multiple answers, print any of them. Examples Input 5 2 2 3 0 5 3 1 5 5 4 Output 3 2 1 5 4 Input 5 2 2 3 0 5 3 1 5 5 1 Output 0 Input 5 1 2 3 0 5 3 4 5 Output 0 Input 5 4 2 3 0 5 3 2 1 3 5 5 2 1 4 Output 3 5 2 1 4 Submitted Solution: ``` class Node: def __init__(self, value): self.value = value self.next = None self.prev = None def __repr__(self): if not self: return "{}()".format(self.__class__.__name__) return "{}({})".format(self.__class__.__name__, self.value) class LL: def __init__(self, iterable=None): self.sentinel = Node(None) self.sentinel.next = self.sentinel self.sentinel.prev = self.sentinel self.__len = 0 if iterable is not None: self += iterable def get_node(self, index): node = sentinel = self.sentinel i = 0 while i <= index: node = node.next if node == sentinel: break i += 1 if node == sentinel: node = None return node def __getitem__(self, index): node = self.get_node(index) return node.value def __len__(self): return self.__len def __setitem__(self, index, value): node = self.get_node(index) node.value = value def __delitem__(self, index): node = self.get_node(index) if node: node.prev.next = node.next if node.next: node.next.prev = node.prev node.prev = None node.next = None node.value = None self.__len -= 1 def __repr__(self): return str(self.to_list()) def to_list(self): l = [] c = self.sentinel.next while c != self.sentinel: l.append(c.value) c = c.next return l def append(self, value): sentinel = self.sentinel node = Node(value) self.insert_between(node, sentinel.prev, sentinel) def appendleft(self, value): sentinel = self.sentinel node = Node(value) self.insert_between(node, sentinel, sentinel.next) def insert(self, index, value): sentinel = self.sentinel new_node = Node(value) len_ = len(self) if len_ == 0: self.insert_between(new_node, sentinel, sentinel) elif index >= 0 and index < len_: node = self.get_node(index) self.insert_between(new_node, node.prev, node) elif index == len_: self.insert_between(new_node, sentinel.prev, sentinel) else: raise IndexError self.__len += 1 def insert_between(self, node, left_node, right_node): if node and left_node and right_node: node.prev = left_node node.next = right_node left_node.next = node right_node.prev = node else: raise IndexError def merge_left(self, other): sentinel = self.sentinel sentinel.next.prev = other.sentinel.prev other.sentinel.prev.next = sentinel.next sentinel.next = other.sentinel.next sentinel.next.prev = sentinel def merge_right(self, other): sentinel = self.sentinel sentinel.prev.next = other.sentinel.next other.sentinel.next.prev = sentinel.prev sentinel.prev = other.sentinel.prev sentinel.prev.next = sentinel import sys,io,os#;Z=io.BytesIO(os.read(0,os.fstat(0).st_size)).readline Z=sys.stdin.readline X=lambda:print(0)or quit() from collections import deque def path(R): H=deque();H.append(R) while P[R]>=0: R=P[R];H.append(R) if len(H)>2:P[H.popleft()]=H[-1] return R N,k=map(int,Z().split());p=[*map(int,Z().split())] K=[-1]*N;P=[-1]*(N//2);S=[1]*(N//2);ch=[];R=0 for _ in range(k): a,b=map(int,Z().split());a-=1;b-=1 if K[a]>=0: if K[b]>=0: va,vb=path(K[a]),path(K[b]) if va!=vb: sa,sb=S[va],S[vb] if sa>sb: P[vb]=va;ch[va].merge_right(ch[vb]);ch[vb]=0 else: P[va]=vb;ch[vb].merge_left(ch[va]);ch[va]=0 if sa==sb:S[vb]+=1 else:X() else:va=path(K[a]);K[b]=va;ch[va].append(b) else: if K[b]>=0:vb=path(K[b]);K[a]=vb;ch[vb].appendleft(a) else: K[a]=R;K[b]=R;R+=1 l=LL();l.append(a);l.append(b) ch.append(l) f=[[]for i in range(N)];x=[-1]*N;h=[0]*N;u=set() for z in ch: if z!=0: c=z.sentinel.next;i=0 while c!=z.sentinel:x[c.value]=i;i+=1;c=c.next for i in range(N): a,b=p[i]-1,i;va,vb=a,b if a<0:z=b;continue if K[a]>=0:va=ch[path(K[a])][0] if K[b]>=0:vb=ch[path(K[b])][0] if va==vb: if x[a]>x[b]:X() else: if(va,vb)not in u:f[va].append(vb);h[vb]+=1;u.add((va,vb)) q=[z];o=[];u=set() while q: v=q.pop() if v in u:X() u.add(v) if x[v]>=0:o+=ch[path(K[v])].to_list() else:o.append(v) for i in f[v]: h[i]-=1 if h[i]<1:q.append(i) if len(o)<N:X() print(' '.join(map(lambda i:str(i+1),o))) ```
instruction
0
1,862
14
3,724
Yes
output
1
1,862
14
3,725
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Ivan is a programming teacher. During the academic year, he plans to give n lectures on n different topics. Each topic should be used in exactly one lecture. Ivan wants to choose which topic will he explain during the 1-st, 2-nd, ..., n-th lecture β€” formally, he wants to choose some permutation of integers from 1 to n (let's call this permutation q). q_i is the index of the topic Ivan will explain during the i-th lecture. For each topic (except exactly one), there exists a prerequisite topic (for the topic i, the prerequisite topic is p_i). Ivan cannot give a lecture on a topic before giving a lecture on its prerequisite topic. There exists at least one valid ordering of topics according to these prerequisite constraints. Ordering the topics correctly can help students understand the lectures better. Ivan has k special pairs of topics (x_i, y_i) such that he knows that the students will understand the y_i-th topic better if the lecture on it is conducted right after the lecture on the x_i-th topic. Ivan wants to satisfy the constraints on every such pair, that is, for every i ∈ [1, k], there should exist some j ∈ [1, n - 1] such that q_j = x_i and q_{j + 1} = y_i. Now Ivan wants to know if there exists an ordering of topics that satisfies all these constraints, and if at least one exists, find any of them. Input The first line contains two integers n and k (2 ≀ n ≀ 3 β‹… 10^5, 1 ≀ k ≀ n - 1) β€” the number of topics and the number of special pairs of topics, respectively. The second line contains n integers p_1, p_2, ..., p_n (0 ≀ p_i ≀ n), where p_i is the prerequisite topic for the topic i (or p_i = 0 if the i-th topic has no prerequisite topics). Exactly one of these integers is 0. At least one ordering of topics such that for every i the p_i-th topic is placed before the i-th topic exists. Then k lines follow, the i-th line contains two integers x_i and y_i (1 ≀ x_i, y_i ≀ n; x_i β‰  y_i) β€” the topics from the i-th special pair. All values of x_i are pairwise distinct; similarly, all valus of y_i are pairwise distinct. Output If there is no ordering of topics meeting all the constraints, print 0. Otherwise, print n pairwise distinct integers q_1, q_2, ..., q_n (1 ≀ q_i ≀ n) β€” the ordering of topics meeting all of the constraints. If there are multiple answers, print any of them. Examples Input 5 2 2 3 0 5 3 1 5 5 4 Output 3 2 1 5 4 Input 5 2 2 3 0 5 3 1 5 5 1 Output 0 Input 5 1 2 3 0 5 3 4 5 Output 0 Input 5 4 2 3 0 5 3 2 1 3 5 5 2 1 4 Output 3 5 2 1 4 Submitted Solution: ``` class Node: def __init__(self, value): self.value = value self.next = None self.prev = None def __repr__(self): if not self: return "{}()".format(self.__class__.__name__) return "{}({})".format(self.__class__.__name__, self.value) class LL: def __init__(self, iterable=None): self.sentinel = Node(None) self.sentinel.next = self.sentinel self.sentinel.prev = self.sentinel self.__len = 0 if iterable is not None: self += iterable def get_node(self, index): node = sentinel = self.sentinel i = 0 while i <= index: node = node.next if node == sentinel: break i += 1 if node == sentinel: node = None return node def __getitem__(self, index): node = self.get_node(index) return node.value def __len__(self): return self.__len def __setitem__(self, index, value): node = self.get_node(index) node.value = value def __delitem__(self, index): node = self.get_node(index) if node: node.prev.next = node.next if node.next: node.next.prev = node.prev node.prev = None node.next = None node.value = None self.__len -= 1 def __repr__(self): return str(self.to_list()) def to_list(self): l = [] c = self.sentinel.next while c != self.sentinel: l.append(c.value) c = c.next return l def append(self, value): sentinel = self.sentinel node = Node(value) self.insert_between(node, sentinel.prev, sentinel) def appendleft(self, value): sentinel = self.sentinel node = Node(value) self.insert_between(node, sentinel, sentinel.next) def insert(self, index, value): sentinel = self.sentinel new_node = Node(value) len_ = len(self) if len_ == 0: self.insert_between(new_node, sentinel, sentinel) elif index >= 0 and index < len_: node = self.get_node(index) self.insert_between(new_node, node.prev, node) elif index == len_: self.insert_between(new_node, sentinel.prev, sentinel) else: raise IndexError self.__len += 1 def insert_between(self, node, left_node, right_node): if node and left_node and right_node: node.prev = left_node node.next = right_node left_node.next = node right_node.prev = node else: raise IndexError def merge_left(self, other): sentinel = self.sentinel sentinel.next.prev = other.sentinel.prev other.sentinel.prev.next = sentinel.next sentinel.next = other.sentinel.next sentinel.next.prev = sentinel def merge_right(self, other): sentinel = self.sentinel sentinel.prev.next = other.sentinel.next other.sentinel.next.prev = sentinel.prev sentinel.prev = other.sentinel.prev sentinel.prev.next = sentinel import sys,io,os;Z=io.BytesIO(os.read(0,os.fstat(0).st_size)).readline X=lambda:print(0)or quit() from collections import deque def path(R): H=deque();H.append(R) while P[R]>=0: R=P[R];H.append(R) if len(H)>2:P[H.popleft()]=H[-1] return R N,k=map(int,Z().split());p=[*map(int,Z().split())] K=[-1]*N;P=[-1]*(N//2);S=[1]*(N//2);ch=[];R=0 for _ in range(k): a,b=map(int,Z().split());a-=1;b-=1 if K[a]>=0: if K[b]>=0: va,vb=path(K[a]),path(K[b]) if va!=vb: sa,sb=S[va],S[vb] if sa>sb: P[vb]=va;ch[va].merge_right(ch[vb]);ch[vb]=0 else: P[va]=vb;ch[vb].merge_left(ch[va]);ch[va]=0 if sa==sb:S[vb]+=1 else:X() else:va=path(K[a]);K[b]=va;ch[va].append(b) else: if K[b]>=0:vb=path(K[b]);K[a]=vb;ch[vb].appendleft(a) else: K[a]=R;K[b]=R;R+=1 l=LL();l.append(a);l.append(b) ch.append(l) f=[[]for i in range(N)];x=[-1]*N;h=[0]*N;u=set() for z in ch: if z!=0: c=z.sentinel.next;i=0 while c!=z.sentinel:x[c.value]=i;i+=1;c=c.next for i in range(N): a,b=p[i]-1,i;va,vb=a,b if a<0:z=b;continue if K[a]>=0:va=ch[path(K[a])][0] if K[b]>=0:vb=ch[path(K[b])][0] if va==vb: if x[a]>x[b]:X() else: if(va,vb)not in u:f[va].append(vb);h[vb]+=1;u.add((va,vb)) q=[z];o=[];u=set() while q: v=q.pop() if v in u:X() u.add(v) if x[v]>=0:o+=ch[path(K[v])].to_list() else:o.append(v) for i in f[v]: h[i]-=1 if h[i]<1:q.append(i) if len(o)<N:X() print(' '.join(map(lambda i:str(i+1),o))) ```
instruction
0
1,863
14
3,726
Yes
output
1
1,863
14
3,727
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Ivan is a programming teacher. During the academic year, he plans to give n lectures on n different topics. Each topic should be used in exactly one lecture. Ivan wants to choose which topic will he explain during the 1-st, 2-nd, ..., n-th lecture β€” formally, he wants to choose some permutation of integers from 1 to n (let's call this permutation q). q_i is the index of the topic Ivan will explain during the i-th lecture. For each topic (except exactly one), there exists a prerequisite topic (for the topic i, the prerequisite topic is p_i). Ivan cannot give a lecture on a topic before giving a lecture on its prerequisite topic. There exists at least one valid ordering of topics according to these prerequisite constraints. Ordering the topics correctly can help students understand the lectures better. Ivan has k special pairs of topics (x_i, y_i) such that he knows that the students will understand the y_i-th topic better if the lecture on it is conducted right after the lecture on the x_i-th topic. Ivan wants to satisfy the constraints on every such pair, that is, for every i ∈ [1, k], there should exist some j ∈ [1, n - 1] such that q_j = x_i and q_{j + 1} = y_i. Now Ivan wants to know if there exists an ordering of topics that satisfies all these constraints, and if at least one exists, find any of them. Input The first line contains two integers n and k (2 ≀ n ≀ 3 β‹… 10^5, 1 ≀ k ≀ n - 1) β€” the number of topics and the number of special pairs of topics, respectively. The second line contains n integers p_1, p_2, ..., p_n (0 ≀ p_i ≀ n), where p_i is the prerequisite topic for the topic i (or p_i = 0 if the i-th topic has no prerequisite topics). Exactly one of these integers is 0. At least one ordering of topics such that for every i the p_i-th topic is placed before the i-th topic exists. Then k lines follow, the i-th line contains two integers x_i and y_i (1 ≀ x_i, y_i ≀ n; x_i β‰  y_i) β€” the topics from the i-th special pair. All values of x_i are pairwise distinct; similarly, all valus of y_i are pairwise distinct. Output If there is no ordering of topics meeting all the constraints, print 0. Otherwise, print n pairwise distinct integers q_1, q_2, ..., q_n (1 ≀ q_i ≀ n) β€” the ordering of topics meeting all of the constraints. If there are multiple answers, print any of them. Examples Input 5 2 2 3 0 5 3 1 5 5 4 Output 3 2 1 5 4 Input 5 2 2 3 0 5 3 1 5 5 1 Output 0 Input 5 1 2 3 0 5 3 4 5 Output 0 Input 5 4 2 3 0 5 3 2 1 3 5 5 2 1 4 Output 3 5 2 1 4 Submitted Solution: ``` import sys input = sys.stdin.readline from collections import deque n,k=map(int,input().split()) P=list(map(int,input().split())) T=[tuple(map(int,input().split())) for i in range(k)] for i in range(n): if P[i]==0: initial=i+1 D=dict() D2=dict() # UnionFind Group = [i for i in range(n+1)] Nodes = [1]*(n+1) def find(x): while Group[x] != x: x=Group[x] return x def Union(x,y): if find(x) != find(y): if Nodes[find(x)] < Nodes[find(y)]: Nodes[find(y)] += Nodes[find(x)] Nodes[find(x)] = 0 Group[find(x)] = find(y) else: Nodes[find(x)] += Nodes[find(y)] Nodes[find(y)] = 0 Group[find(y)] = find(x) for x,y in T: Union(x,y) if x in D: print(0) sys.exit() if y in D2: print(0) sys.exit() if y==initial: print(0) sys.exit() D[x]=y D2[y]=x E=[set() for i in range(n+1)] for i in range(n): if P[i]==0: initial=i+1 elif P[i] in D2 and D2[P[i]]==i+1: print(0) sys.exit() else: E[find(P[i])].add(find(i+1)) EDGEIN=[0]*(n+1) for i in range(n+1): for to in E[i]: if find(i)==find(to): continue EDGEIN[to]+=1 Q=[] for i in range(1,n+1): if find(i)!=i: continue if EDGEIN[i]==0: Q.append(i) ANS=[] USE=[0]*(n+1) while Q: #print(Q,ANS) x=Q.pop() if USE[x]==1: print(0) sys.exit() else: #ANS.append(x) USE[x]=0 z=x count=0 while z in D2: z=D2[z] count+=1 if count>n+5: print(0) sys.exit() ANS.append(z) while z in D: if USE[D[z]]==0: ANS.append(D[z]) z=D[z] USE[z]=1 else: print(0) sys.exit() for to in E[x]: EDGEIN[to]-=1 if EDGEIN[to]==0: Q.append(to) if len(ANS)==n: print(*ANS) else: print(0) ```
instruction
0
1,864
14
3,728
Yes
output
1
1,864
14
3,729
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Ivan is a programming teacher. During the academic year, he plans to give n lectures on n different topics. Each topic should be used in exactly one lecture. Ivan wants to choose which topic will he explain during the 1-st, 2-nd, ..., n-th lecture β€” formally, he wants to choose some permutation of integers from 1 to n (let's call this permutation q). q_i is the index of the topic Ivan will explain during the i-th lecture. For each topic (except exactly one), there exists a prerequisite topic (for the topic i, the prerequisite topic is p_i). Ivan cannot give a lecture on a topic before giving a lecture on its prerequisite topic. There exists at least one valid ordering of topics according to these prerequisite constraints. Ordering the topics correctly can help students understand the lectures better. Ivan has k special pairs of topics (x_i, y_i) such that he knows that the students will understand the y_i-th topic better if the lecture on it is conducted right after the lecture on the x_i-th topic. Ivan wants to satisfy the constraints on every such pair, that is, for every i ∈ [1, k], there should exist some j ∈ [1, n - 1] such that q_j = x_i and q_{j + 1} = y_i. Now Ivan wants to know if there exists an ordering of topics that satisfies all these constraints, and if at least one exists, find any of them. Input The first line contains two integers n and k (2 ≀ n ≀ 3 β‹… 10^5, 1 ≀ k ≀ n - 1) β€” the number of topics and the number of special pairs of topics, respectively. The second line contains n integers p_1, p_2, ..., p_n (0 ≀ p_i ≀ n), where p_i is the prerequisite topic for the topic i (or p_i = 0 if the i-th topic has no prerequisite topics). Exactly one of these integers is 0. At least one ordering of topics such that for every i the p_i-th topic is placed before the i-th topic exists. Then k lines follow, the i-th line contains two integers x_i and y_i (1 ≀ x_i, y_i ≀ n; x_i β‰  y_i) β€” the topics from the i-th special pair. All values of x_i are pairwise distinct; similarly, all valus of y_i are pairwise distinct. Output If there is no ordering of topics meeting all the constraints, print 0. Otherwise, print n pairwise distinct integers q_1, q_2, ..., q_n (1 ≀ q_i ≀ n) β€” the ordering of topics meeting all of the constraints. If there are multiple answers, print any of them. Examples Input 5 2 2 3 0 5 3 1 5 5 4 Output 3 2 1 5 4 Input 5 2 2 3 0 5 3 1 5 5 1 Output 0 Input 5 1 2 3 0 5 3 4 5 Output 0 Input 5 4 2 3 0 5 3 2 1 3 5 5 2 1 4 Output 3 5 2 1 4 Submitted Solution: ``` import sys input = sys.stdin.readline from collections import deque n,k=map(int,input().split()) P=list(map(int,input().split())) T=[tuple(map(int,input().split())) for i in range(k)] E=[[] for i in range(n+1)] EFROM=[[] for i in range(n+1)] for i in range(n): if P[i]==0: initial=i+1 else: E[P[i]].append(i+1) EFROM[i+1].append(P[i]) D=dict() D2=dict() for x,y in T: if x in D: print(0) sys.exit() if y in D2: print(0) sys.exit() if y==initial: print(0) sys.exit() D[x]=y D2[y]=x EDGEOUT=[0]*(n+1) for i in range(n+1): for to in E[i]: EDGEOUT[i]+=1 for x,y in T: EDGEOUT[x]+=1 Q=[] Q2=[] QSOON=-1 for i in range(n+1): if EDGEOUT[i]==0 and i!=0: if i in D: continue if i in D2: Q2.append(i) else: Q.append(i) ANS=[] USE=[0]*(n+1) while Q or Q2 or QSOON!=-1: #print(Q,Q2,QSOON) if QSOON!=-1: x=QSOON QSOON=-1 if USE[x]==1: print(0) sys.exit() USE[x]=1 ANS.append(x) fr=P[x-1] EDGEOUT[fr]-=1 if x in D2: QSOON=D2[x] EDGEOUT[D2[x]]-=1 if D2[x]==fr: continue else: if EDGEOUT[fr]==0: if fr in D2: Q2.append(fr) else: Q.append(fr) else: if EDGEOUT[fr]==0: if fr in D2: Q2.append(fr) else: Q.append(fr) elif Q: x=Q.pop() if USE[x]==1: continue USE[x]=1 ANS.append(x) fr=P[x-1] EDGEOUT[fr]-=1 if EDGEOUT[fr]==0: if fr in D2: Q2.append(fr) else: Q.append(fr) else: x=Q2.pop() if USE[x]==1: continue USE[x]=1 ANS.append(x) fr=P[x-1] EDGEOUT[fr]-=1 QSOON=D2[x] EDGEOUT[D2[x]]-=1 if D2[x]==fr: continue else: if EDGEOUT[fr]==0: if fr in D2: Q2.append(fr) else: Q.append(fr) ANS.reverse() if len(ANS)==n: USE=[0]*(n+1) for i in range(n-1,-1,-1): if USE[P[ANS[i]-1]]==1: print(0) sys.exit() USE[ANS[i]]=1 print(*ANS) else: print(0) ```
instruction
0
1,865
14
3,730
No
output
1
1,865
14
3,731
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Ivan is a programming teacher. During the academic year, he plans to give n lectures on n different topics. Each topic should be used in exactly one lecture. Ivan wants to choose which topic will he explain during the 1-st, 2-nd, ..., n-th lecture β€” formally, he wants to choose some permutation of integers from 1 to n (let's call this permutation q). q_i is the index of the topic Ivan will explain during the i-th lecture. For each topic (except exactly one), there exists a prerequisite topic (for the topic i, the prerequisite topic is p_i). Ivan cannot give a lecture on a topic before giving a lecture on its prerequisite topic. There exists at least one valid ordering of topics according to these prerequisite constraints. Ordering the topics correctly can help students understand the lectures better. Ivan has k special pairs of topics (x_i, y_i) such that he knows that the students will understand the y_i-th topic better if the lecture on it is conducted right after the lecture on the x_i-th topic. Ivan wants to satisfy the constraints on every such pair, that is, for every i ∈ [1, k], there should exist some j ∈ [1, n - 1] such that q_j = x_i and q_{j + 1} = y_i. Now Ivan wants to know if there exists an ordering of topics that satisfies all these constraints, and if at least one exists, find any of them. Input The first line contains two integers n and k (2 ≀ n ≀ 3 β‹… 10^5, 1 ≀ k ≀ n - 1) β€” the number of topics and the number of special pairs of topics, respectively. The second line contains n integers p_1, p_2, ..., p_n (0 ≀ p_i ≀ n), where p_i is the prerequisite topic for the topic i (or p_i = 0 if the i-th topic has no prerequisite topics). Exactly one of these integers is 0. At least one ordering of topics such that for every i the p_i-th topic is placed before the i-th topic exists. Then k lines follow, the i-th line contains two integers x_i and y_i (1 ≀ x_i, y_i ≀ n; x_i β‰  y_i) β€” the topics from the i-th special pair. All values of x_i are pairwise distinct; similarly, all valus of y_i are pairwise distinct. Output If there is no ordering of topics meeting all the constraints, print 0. Otherwise, print n pairwise distinct integers q_1, q_2, ..., q_n (1 ≀ q_i ≀ n) β€” the ordering of topics meeting all of the constraints. If there are multiple answers, print any of them. Examples Input 5 2 2 3 0 5 3 1 5 5 4 Output 3 2 1 5 4 Input 5 2 2 3 0 5 3 1 5 5 1 Output 0 Input 5 1 2 3 0 5 3 4 5 Output 0 Input 5 4 2 3 0 5 3 2 1 3 5 5 2 1 4 Output 3 5 2 1 4 Submitted Solution: ``` import io import os from collections import defaultdict input = io.BytesIO(os.read(0, os.fstat(0).st_size)).readline def toposort(g): inc = {} for x in g: inc[x] = 0 for l in g.values(): for y in l: inc[y] += 1 no_inc = [x for x in g if inc[x] == 0] ans = [] found = 0 while no_inc: x = no_inc.pop() ans.append(x) found += 1 for nei in g[x]: inc[nei] -= 1 if inc[nei] == 0: no_inc.append(nei) if found < len(g): return None return ans def solve(): n, k = map(int, input().split()) p = list(map(int, input().split())) edges = [] for _ in range(k): x, y = map(int, input().split()) x -= 1 y -= 1 edges.append((x, y)) g = {i: set() for i in range(n)} for x, y in edges: g[x].add(y) for i, v in enumerate(p): if v != 0: g[v-1].add(i) ans = toposort(g) if ans is None: print(0) return next = [-1] * n inc = [0] * n for x, y in edges: next[x] = y inc[y] += 1 no_inc = [v for v in range(n) if inc[v] == 0] rep = list(range(n)) while no_inc: v = no_inc.pop() if next[v] != -1: rep[next[v]] = rep[v] no_inc.append(next[v]) g = {x: set() for x in set(rep)} for i, v in enumerate(p): if v != 0: if rep[v-1] != rep[i]: g[rep[v-1]].add(rep[i]) ans = toposort(g) if ans is None: print(0, 1) return final_ans = [] for x in ans: final_ans.append(x) while next[x] != -1: x = next[x] final_ans.append(x) print(*[x+1 for x in final_ans]) t = 1 for _ in range(t): solve() ```
instruction
0
1,866
14
3,732
No
output
1
1,866
14
3,733
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Ivan is a programming teacher. During the academic year, he plans to give n lectures on n different topics. Each topic should be used in exactly one lecture. Ivan wants to choose which topic will he explain during the 1-st, 2-nd, ..., n-th lecture β€” formally, he wants to choose some permutation of integers from 1 to n (let's call this permutation q). q_i is the index of the topic Ivan will explain during the i-th lecture. For each topic (except exactly one), there exists a prerequisite topic (for the topic i, the prerequisite topic is p_i). Ivan cannot give a lecture on a topic before giving a lecture on its prerequisite topic. There exists at least one valid ordering of topics according to these prerequisite constraints. Ordering the topics correctly can help students understand the lectures better. Ivan has k special pairs of topics (x_i, y_i) such that he knows that the students will understand the y_i-th topic better if the lecture on it is conducted right after the lecture on the x_i-th topic. Ivan wants to satisfy the constraints on every such pair, that is, for every i ∈ [1, k], there should exist some j ∈ [1, n - 1] such that q_j = x_i and q_{j + 1} = y_i. Now Ivan wants to know if there exists an ordering of topics that satisfies all these constraints, and if at least one exists, find any of them. Input The first line contains two integers n and k (2 ≀ n ≀ 3 β‹… 10^5, 1 ≀ k ≀ n - 1) β€” the number of topics and the number of special pairs of topics, respectively. The second line contains n integers p_1, p_2, ..., p_n (0 ≀ p_i ≀ n), where p_i is the prerequisite topic for the topic i (or p_i = 0 if the i-th topic has no prerequisite topics). Exactly one of these integers is 0. At least one ordering of topics such that for every i the p_i-th topic is placed before the i-th topic exists. Then k lines follow, the i-th line contains two integers x_i and y_i (1 ≀ x_i, y_i ≀ n; x_i β‰  y_i) β€” the topics from the i-th special pair. All values of x_i are pairwise distinct; similarly, all valus of y_i are pairwise distinct. Output If there is no ordering of topics meeting all the constraints, print 0. Otherwise, print n pairwise distinct integers q_1, q_2, ..., q_n (1 ≀ q_i ≀ n) β€” the ordering of topics meeting all of the constraints. If there are multiple answers, print any of them. Examples Input 5 2 2 3 0 5 3 1 5 5 4 Output 3 2 1 5 4 Input 5 2 2 3 0 5 3 1 5 5 1 Output 0 Input 5 1 2 3 0 5 3 4 5 Output 0 Input 5 4 2 3 0 5 3 2 1 3 5 5 2 1 4 Output 3 5 2 1 4 Submitted Solution: ``` import io import os from collections import defaultdict #input = io.BytesIO(os.read(0, os.fstat(0).st_size)).readline def toposort(g): inc = {} for x in g: inc[x] = 0 for l in g.values(): for y in l: inc[y] += 1 no_inc = [x for x in g if inc[x] == 0] ans = [] found = 0 while no_inc: x = no_inc.pop() ans.append(x) found += 1 for nei in g[x]: inc[nei] -= 1 if inc[nei] == 0: no_inc.append(nei) if found < len(g): return None return ans def solve(): n, k = map(int, input().split()) p = list(map(int, input().split())) edges = [] for _ in range(k): x, y = map(int, input().split()) x -= 1 y -= 1 edges.append((x, y)) g = {i: set() for i in range(n)} for x, y in edges: g[x].add(y) for i, v in enumerate(p): if v != 0: g[v-1].add(i) ans = toposort(g) if ans is None: print(0) return next = [-1] * n inc = [0] * n for i, v in enumerate(p): if v != 0: g[v-1] = i inc[i] += 1 no_inc = [v for v in range(n) if inc[v] == 0] rep = list(range(n)) while no_inc: v = no_inc.pop() if next[v] != -1: rep[next[v]] = rep[v] g = {x: set() for x in set(rep)} for x, y in edges: g[rep[x]].add(rep[y]) ans = toposort(g) if ans is None: print(0) return final_ans = [] for x in ans: final_ans.append(x) while next[x] != -1: x = next[x] final_ans.append(x) print(*[x+1 for x in final_ans]) t = 1 for _ in range(t): solve() ```
instruction
0
1,867
14
3,734
No
output
1
1,867
14
3,735
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Ivan is a programming teacher. During the academic year, he plans to give n lectures on n different topics. Each topic should be used in exactly one lecture. Ivan wants to choose which topic will he explain during the 1-st, 2-nd, ..., n-th lecture β€” formally, he wants to choose some permutation of integers from 1 to n (let's call this permutation q). q_i is the index of the topic Ivan will explain during the i-th lecture. For each topic (except exactly one), there exists a prerequisite topic (for the topic i, the prerequisite topic is p_i). Ivan cannot give a lecture on a topic before giving a lecture on its prerequisite topic. There exists at least one valid ordering of topics according to these prerequisite constraints. Ordering the topics correctly can help students understand the lectures better. Ivan has k special pairs of topics (x_i, y_i) such that he knows that the students will understand the y_i-th topic better if the lecture on it is conducted right after the lecture on the x_i-th topic. Ivan wants to satisfy the constraints on every such pair, that is, for every i ∈ [1, k], there should exist some j ∈ [1, n - 1] such that q_j = x_i and q_{j + 1} = y_i. Now Ivan wants to know if there exists an ordering of topics that satisfies all these constraints, and if at least one exists, find any of them. Input The first line contains two integers n and k (2 ≀ n ≀ 3 β‹… 10^5, 1 ≀ k ≀ n - 1) β€” the number of topics and the number of special pairs of topics, respectively. The second line contains n integers p_1, p_2, ..., p_n (0 ≀ p_i ≀ n), where p_i is the prerequisite topic for the topic i (or p_i = 0 if the i-th topic has no prerequisite topics). Exactly one of these integers is 0. At least one ordering of topics such that for every i the p_i-th topic is placed before the i-th topic exists. Then k lines follow, the i-th line contains two integers x_i and y_i (1 ≀ x_i, y_i ≀ n; x_i β‰  y_i) β€” the topics from the i-th special pair. All values of x_i are pairwise distinct; similarly, all valus of y_i are pairwise distinct. Output If there is no ordering of topics meeting all the constraints, print 0. Otherwise, print n pairwise distinct integers q_1, q_2, ..., q_n (1 ≀ q_i ≀ n) β€” the ordering of topics meeting all of the constraints. If there are multiple answers, print any of them. Examples Input 5 2 2 3 0 5 3 1 5 5 4 Output 3 2 1 5 4 Input 5 2 2 3 0 5 3 1 5 5 1 Output 0 Input 5 1 2 3 0 5 3 4 5 Output 0 Input 5 4 2 3 0 5 3 2 1 3 5 5 2 1 4 Output 3 5 2 1 4 Submitted Solution: ``` import sys input = sys.stdin.readline from collections import deque n,k=map(int,input().split()) P=list(map(int,input().split())) T=[tuple(map(int,input().split())) for i in range(k)] E=[[] for i in range(n+1)] for i in range(n): if P[i]==0: initial=i+1 else: E[P[i]].append(i+1) D=dict() D2=dict() for x,y in T: if x in D: print(0) sys.exit() if y in D2: print(0) sys.exit() D[x]=y D2[y]=x ANS=[] Q=deque([initial]) while Q: x=Q.popleft() ANS.append(x) if x in D: Q.appendleft(D[x]) continue for to in E[x]: if to in D2: continue else: Q.append(to) if len(ANS)==n: print(*ANS) else: print(0) ```
instruction
0
1,868
14
3,736
No
output
1
1,868
14
3,737
Provide tags and a correct Python 3 solution for this coding contest problem. During her tantrums the princess usually smashes some collectable porcelain. Every furious shriek is accompanied with one item smashed. The collection of porcelain is arranged neatly on n shelves. Within each shelf the items are placed in one row, so that one can access only the outermost items β€” the leftmost or the rightmost item, not the ones in the middle of the shelf. Once an item is taken, the next item on that side of the shelf can be accessed (see example). Once an item is taken, it can't be returned to the shelves. You are given the values of all items. Your task is to find the maximal damage the princess' tantrum of m shrieks can inflict on the collection of porcelain. Input The first line of input data contains two integers n (1 ≀ n ≀ 100) and m (1 ≀ m ≀ 10000). The next n lines contain the values of the items on the shelves: the first number gives the number of items on this shelf (an integer between 1 and 100, inclusive), followed by the values of the items (integers between 1 and 100, inclusive), in the order in which they appear on the shelf (the first number corresponds to the leftmost item, the last one β€” to the rightmost one). The total number of items is guaranteed to be at least m. Output Output the maximal total value of a tantrum of m shrieks. Examples Input 2 3 3 3 7 2 3 4 1 5 Output 15 Input 1 3 4 4 3 1 2 Output 9 Note In the first case there are two shelves, each with three items. To maximize the total value of the items chosen, one can take two items from the left side of the first shelf and one item from the right side of the second shelf. In the second case there is only one shelf, so all three items are taken from it β€” two from the left side and one from the right side.
instruction
0
1,869
14
3,738
Tags: dp Correct Solution: ``` f = lambda: map(int, input().split()) n, m = f() u = [0] for i in range(n): t = list(f()) k = t[0] for i in range(1, k): t[i + 1] += t[i] v = [t[k]] * (k + 1) v[0] = t[0] = 0 for d in range(1, k): v[k - d] -= min(t[j + d] - t[j] for j in range(k - d + 1)) p = [0] * (min(m, len(u) + len(v)) + 1) for i, x in enumerate(u): for j, y in enumerate(v, i): if j > m: break p[j] = max(p[j], x + y) u = p print(u[m]) ```
output
1
1,869
14
3,739
Provide tags and a correct Python 3 solution for this coding contest problem. During her tantrums the princess usually smashes some collectable porcelain. Every furious shriek is accompanied with one item smashed. The collection of porcelain is arranged neatly on n shelves. Within each shelf the items are placed in one row, so that one can access only the outermost items β€” the leftmost or the rightmost item, not the ones in the middle of the shelf. Once an item is taken, the next item on that side of the shelf can be accessed (see example). Once an item is taken, it can't be returned to the shelves. You are given the values of all items. Your task is to find the maximal damage the princess' tantrum of m shrieks can inflict on the collection of porcelain. Input The first line of input data contains two integers n (1 ≀ n ≀ 100) and m (1 ≀ m ≀ 10000). The next n lines contain the values of the items on the shelves: the first number gives the number of items on this shelf (an integer between 1 and 100, inclusive), followed by the values of the items (integers between 1 and 100, inclusive), in the order in which they appear on the shelf (the first number corresponds to the leftmost item, the last one β€” to the rightmost one). The total number of items is guaranteed to be at least m. Output Output the maximal total value of a tantrum of m shrieks. Examples Input 2 3 3 3 7 2 3 4 1 5 Output 15 Input 1 3 4 4 3 1 2 Output 9 Note In the first case there are two shelves, each with three items. To maximize the total value of the items chosen, one can take two items from the left side of the first shelf and one item from the right side of the second shelf. In the second case there is only one shelf, so all three items are taken from it β€” two from the left side and one from the right side.
instruction
0
1,870
14
3,740
Tags: dp Correct Solution: ``` def mem(ind,j): if(ind == n): return 0 if(dp2[ind][j] != -1): return dp2[ind][j] ans = 0 for i in range(min(j,sz[ind])+1): ans = max(ans,dp[ind][i]+mem(ind+1,j-i)) dp2[ind][j] = ans return ans n,m = map(int,input().split()) sz = [0 for i in range(n)] dp = [] for y in range(n): a = list(map(int,input().split())) sz[y] = a[0] pre = [a[1]] for i in range(2,sz[y]+1): pre.append(a[i]+pre[-1]) s = sum(a[1:]) dp1 = [0 for j in range(sz[y]+1)] dp1[sz[y]] = s for i in range(sz[y]): for j in range(i,sz[y]): if(i != 0): dp1[sz[y]-(j-i+1)] = max(dp1[sz[y]-(j-i+1)],s-pre[j]+pre[i-1]) else: dp1[sz[y]-(j-i+1)] = max(dp1[sz[y]-(j-i+1)],s-pre[j]) dp.append(dp1) dp2 = [[-1 for i in range(m+1)] for j in range(n)] print(mem(0,m)) ```
output
1
1,870
14
3,741
Provide tags and a correct Python 3 solution for this coding contest problem. During her tantrums the princess usually smashes some collectable porcelain. Every furious shriek is accompanied with one item smashed. The collection of porcelain is arranged neatly on n shelves. Within each shelf the items are placed in one row, so that one can access only the outermost items β€” the leftmost or the rightmost item, not the ones in the middle of the shelf. Once an item is taken, the next item on that side of the shelf can be accessed (see example). Once an item is taken, it can't be returned to the shelves. You are given the values of all items. Your task is to find the maximal damage the princess' tantrum of m shrieks can inflict on the collection of porcelain. Input The first line of input data contains two integers n (1 ≀ n ≀ 100) and m (1 ≀ m ≀ 10000). The next n lines contain the values of the items on the shelves: the first number gives the number of items on this shelf (an integer between 1 and 100, inclusive), followed by the values of the items (integers between 1 and 100, inclusive), in the order in which they appear on the shelf (the first number corresponds to the leftmost item, the last one β€” to the rightmost one). The total number of items is guaranteed to be at least m. Output Output the maximal total value of a tantrum of m shrieks. Examples Input 2 3 3 3 7 2 3 4 1 5 Output 15 Input 1 3 4 4 3 1 2 Output 9 Note In the first case there are two shelves, each with three items. To maximize the total value of the items chosen, one can take two items from the left side of the first shelf and one item from the right side of the second shelf. In the second case there is only one shelf, so all three items are taken from it β€” two from the left side and one from the right side.
instruction
0
1,871
14
3,742
Tags: dp Correct Solution: ``` f = lambda: list(map(int, input().split())) def g(t): n = t[0] for i in range(1, n): t[i + 1] += t[i] p = [t[n]] * (n + 1) p[n] = t[0] = 0 for d in range(1, n): p[d] -= min(t[j + d] - t[j] for j in range(n - d + 1)) return p[::-1] n, m = f() u = g(f()) for i in range(n - 1): v = g(f()) p = [0] * (min(m, len(u) + len(v)) + 1) for i, x in enumerate(u): for j, y in enumerate(v, i): if j > m: break p[j] = max(p[j], x + y) u = p print(u[m]) ```
output
1
1,871
14
3,743
Provide tags and a correct Python 3 solution for this coding contest problem. During her tantrums the princess usually smashes some collectable porcelain. Every furious shriek is accompanied with one item smashed. The collection of porcelain is arranged neatly on n shelves. Within each shelf the items are placed in one row, so that one can access only the outermost items β€” the leftmost or the rightmost item, not the ones in the middle of the shelf. Once an item is taken, the next item on that side of the shelf can be accessed (see example). Once an item is taken, it can't be returned to the shelves. You are given the values of all items. Your task is to find the maximal damage the princess' tantrum of m shrieks can inflict on the collection of porcelain. Input The first line of input data contains two integers n (1 ≀ n ≀ 100) and m (1 ≀ m ≀ 10000). The next n lines contain the values of the items on the shelves: the first number gives the number of items on this shelf (an integer between 1 and 100, inclusive), followed by the values of the items (integers between 1 and 100, inclusive), in the order in which they appear on the shelf (the first number corresponds to the leftmost item, the last one β€” to the rightmost one). The total number of items is guaranteed to be at least m. Output Output the maximal total value of a tantrum of m shrieks. Examples Input 2 3 3 3 7 2 3 4 1 5 Output 15 Input 1 3 4 4 3 1 2 Output 9 Note In the first case there are two shelves, each with three items. To maximize the total value of the items chosen, one can take two items from the left side of the first shelf and one item from the right side of the second shelf. In the second case there is only one shelf, so all three items are taken from it β€” two from the left side and one from the right side.
instruction
0
1,872
14
3,744
Tags: dp Correct Solution: ``` import io, os input = io.StringIO(os.read(0, os.fstat(0).st_size).decode()).readline n, m = map(int, input().split()) dp = [0] * (m + 1) for i in range(n): a = list(map(int, input().split())) t = sum(a[1:]) b = [0] * (a[0] + 1) b[-1] = t for i in range(0, len(a)): s = t for j in range(i + 1, len(a)): s -= a[j] b[a[0] - j + i] = max(b[a[0] - j + i], s) for x in range(m, -1, -1): for y in range(1, min(x, a[0]) + 1): dp[x] = max(dp[x], dp[x - y] + b[y]) print(dp[m]) ```
output
1
1,872
14
3,745
Provide tags and a correct Python 3 solution for this coding contest problem. During her tantrums the princess usually smashes some collectable porcelain. Every furious shriek is accompanied with one item smashed. The collection of porcelain is arranged neatly on n shelves. Within each shelf the items are placed in one row, so that one can access only the outermost items β€” the leftmost or the rightmost item, not the ones in the middle of the shelf. Once an item is taken, the next item on that side of the shelf can be accessed (see example). Once an item is taken, it can't be returned to the shelves. You are given the values of all items. Your task is to find the maximal damage the princess' tantrum of m shrieks can inflict on the collection of porcelain. Input The first line of input data contains two integers n (1 ≀ n ≀ 100) and m (1 ≀ m ≀ 10000). The next n lines contain the values of the items on the shelves: the first number gives the number of items on this shelf (an integer between 1 and 100, inclusive), followed by the values of the items (integers between 1 and 100, inclusive), in the order in which they appear on the shelf (the first number corresponds to the leftmost item, the last one β€” to the rightmost one). The total number of items is guaranteed to be at least m. Output Output the maximal total value of a tantrum of m shrieks. Examples Input 2 3 3 3 7 2 3 4 1 5 Output 15 Input 1 3 4 4 3 1 2 Output 9 Note In the first case there are two shelves, each with three items. To maximize the total value of the items chosen, one can take two items from the left side of the first shelf and one item from the right side of the second shelf. In the second case there is only one shelf, so all three items are taken from it β€” two from the left side and one from the right side.
instruction
0
1,873
14
3,746
Tags: dp Correct Solution: ``` f = lambda: list(map(int, input().split())) def g(t): n = t[0] t[0] = 0 for i in range(1, n): t[i + 1] += t[i] p = [t[n]] * (n + 1) p[n] = 0 for d in range(1, n): p[d] -= min(t[j + d] - t[j] for j in range(n - d + 1)) p.reverse() return p def h(u): v = g(f()) p = [0] * (min(m, len(u) + len(v)) + 1) for i, x in enumerate(u): for j, y in enumerate(v): if i + j > m: break p[i + j] = max(p[i + j], x + y) return p n, m = f() u = g(f()) for i in range(n - 1): u = h(u) print(u[m]) ```
output
1
1,873
14
3,747
Provide tags and a correct Python 3 solution for this coding contest problem. During her tantrums the princess usually smashes some collectable porcelain. Every furious shriek is accompanied with one item smashed. The collection of porcelain is arranged neatly on n shelves. Within each shelf the items are placed in one row, so that one can access only the outermost items β€” the leftmost or the rightmost item, not the ones in the middle of the shelf. Once an item is taken, the next item on that side of the shelf can be accessed (see example). Once an item is taken, it can't be returned to the shelves. You are given the values of all items. Your task is to find the maximal damage the princess' tantrum of m shrieks can inflict on the collection of porcelain. Input The first line of input data contains two integers n (1 ≀ n ≀ 100) and m (1 ≀ m ≀ 10000). The next n lines contain the values of the items on the shelves: the first number gives the number of items on this shelf (an integer between 1 and 100, inclusive), followed by the values of the items (integers between 1 and 100, inclusive), in the order in which they appear on the shelf (the first number corresponds to the leftmost item, the last one β€” to the rightmost one). The total number of items is guaranteed to be at least m. Output Output the maximal total value of a tantrum of m shrieks. Examples Input 2 3 3 3 7 2 3 4 1 5 Output 15 Input 1 3 4 4 3 1 2 Output 9 Note In the first case there are two shelves, each with three items. To maximize the total value of the items chosen, one can take two items from the left side of the first shelf and one item from the right side of the second shelf. In the second case there is only one shelf, so all three items are taken from it β€” two from the left side and one from the right side.
instruction
0
1,874
14
3,748
Tags: dp Correct Solution: ``` #!/usr/bin/env python3 import os import sys from io import BytesIO, IOBase class FastO: def __init__(self, fd=1): stream = BytesIO() self.flush = lambda: os.write(fd, stream.getvalue()) and not stream.truncate(0) and stream.seek(0) self.write = lambda b: stream.write(b.encode()) class ostream: def __lshift__(self, a): sys.stdout.write(str(a)) return self sys.stdout, cout = FastO(), ostream() numbers, num, sign = [], 0, True for char in os.read(0, os.fstat(0).st_size): if char >= 48: num = num * 10 + char - 48 elif char == 45: sign = False elif char != 13: numbers.append(num if sign else -num) num, sign = 0, True if char >= 48: numbers.append(num if sign else -num) getnum = iter(numbers).__next__ def main(): n, m = getnum(), getnum() _dp = [[] for _ in range(n)] for i in range(n): ni = getnum() ai = [getnum() for _ in range(ni)] cumsum = [0] * (ni + 1) for j in range(ni): cumsum[j + 1] = cumsum[j] + ai[j] _dpi = [0] * (ni + 1) for j in range(ni + 1): for k in range(j, ni + 1): _dpi[ni + j - k] = max(_dpi[ni + j - k], cumsum[j] + cumsum[-1] - cumsum[k]) _dp[i] = _dpi dp = [0] * (m + 1) for i in range(n): for j in reversed(range(m + 1)): for k in range(min(len(_dp[i]), j + 1)): dp[j] = max(dp[j], _dp[i][k] + dp[j - k]) cout << dp[m] if __name__ == '__main__': main() ```
output
1
1,874
14
3,749
Provide tags and a correct Python 3 solution for this coding contest problem. During her tantrums the princess usually smashes some collectable porcelain. Every furious shriek is accompanied with one item smashed. The collection of porcelain is arranged neatly on n shelves. Within each shelf the items are placed in one row, so that one can access only the outermost items β€” the leftmost or the rightmost item, not the ones in the middle of the shelf. Once an item is taken, the next item on that side of the shelf can be accessed (see example). Once an item is taken, it can't be returned to the shelves. You are given the values of all items. Your task is to find the maximal damage the princess' tantrum of m shrieks can inflict on the collection of porcelain. Input The first line of input data contains two integers n (1 ≀ n ≀ 100) and m (1 ≀ m ≀ 10000). The next n lines contain the values of the items on the shelves: the first number gives the number of items on this shelf (an integer between 1 and 100, inclusive), followed by the values of the items (integers between 1 and 100, inclusive), in the order in which they appear on the shelf (the first number corresponds to the leftmost item, the last one β€” to the rightmost one). The total number of items is guaranteed to be at least m. Output Output the maximal total value of a tantrum of m shrieks. Examples Input 2 3 3 3 7 2 3 4 1 5 Output 15 Input 1 3 4 4 3 1 2 Output 9 Note In the first case there are two shelves, each with three items. To maximize the total value of the items chosen, one can take two items from the left side of the first shelf and one item from the right side of the second shelf. In the second case there is only one shelf, so all three items are taken from it β€” two from the left side and one from the right side.
instruction
0
1,875
14
3,750
Tags: dp Correct Solution: ``` #!/usr/bin/env python3 import os import sys from io import BytesIO, IOBase class FastO: def __init__(self, fd=1): stream = BytesIO() self.flush = lambda: os.write(fd, stream.getvalue()) and not stream.truncate(0) and stream.seek(0) self.write = lambda b: stream.write(b.encode()) class ostream: def __lshift__(self, a): sys.stdout.write(str(a)) return self sys.stdout, cout = FastO(), ostream() numbers, num, sign = [], 0, True for char in os.read(0, os.fstat(0).st_size): if char >= 48: num = num * 10 + char - 48 elif char == 45: sign = False elif char != 13: numbers.append(num if sign else -num) num, sign = 0, True if char >= 48: numbers.append(num if sign else -num) getnum = numbers[::-1].pop def main(): n, m = getnum(), getnum() _dp = [[] for _ in range(n)] for i in range(n): ni = getnum() ai = [getnum() for _ in range(ni)] cumsum = [0] * (ni + 1) for j in range(ni): cumsum[j + 1] = cumsum[j] + ai[j] _dpi = [0] * (ni + 1) for j in range(ni + 1): for k in range(j, ni + 1): _dpi[ni + j - k] = max(_dpi[ni + j - k], cumsum[j] + cumsum[-1] - cumsum[k]) _dp[i] = _dpi dp = [0] * (m + 1) for i in range(n): _dpi = _dp[i] for j in reversed(range(m + 1)): dpj = dp[j] for k in range(min(len(_dp[i]), j + 1)): dpj = max(dpj, _dpi[k] + dp[j - k]) dp[j] = dpj cout << dp[m] if __name__ == '__main__': main() ```
output
1
1,875
14
3,751
Provide tags and a correct Python 3 solution for this coding contest problem. During her tantrums the princess usually smashes some collectable porcelain. Every furious shriek is accompanied with one item smashed. The collection of porcelain is arranged neatly on n shelves. Within each shelf the items are placed in one row, so that one can access only the outermost items β€” the leftmost or the rightmost item, not the ones in the middle of the shelf. Once an item is taken, the next item on that side of the shelf can be accessed (see example). Once an item is taken, it can't be returned to the shelves. You are given the values of all items. Your task is to find the maximal damage the princess' tantrum of m shrieks can inflict on the collection of porcelain. Input The first line of input data contains two integers n (1 ≀ n ≀ 100) and m (1 ≀ m ≀ 10000). The next n lines contain the values of the items on the shelves: the first number gives the number of items on this shelf (an integer between 1 and 100, inclusive), followed by the values of the items (integers between 1 and 100, inclusive), in the order in which they appear on the shelf (the first number corresponds to the leftmost item, the last one β€” to the rightmost one). The total number of items is guaranteed to be at least m. Output Output the maximal total value of a tantrum of m shrieks. Examples Input 2 3 3 3 7 2 3 4 1 5 Output 15 Input 1 3 4 4 3 1 2 Output 9 Note In the first case there are two shelves, each with three items. To maximize the total value of the items chosen, one can take two items from the left side of the first shelf and one item from the right side of the second shelf. In the second case there is only one shelf, so all three items are taken from it β€” two from the left side and one from the right side.
instruction
0
1,876
14
3,752
Tags: dp Correct Solution: ``` #!/usr/bin/env python3 import os import sys from io import BytesIO, IOBase class FastO: def __init__(self, fd=1): stream = BytesIO() self.flush = lambda: os.write(fd, stream.getvalue()) and not stream.truncate(0) and stream.seek(0) self.write = lambda b: stream.write(b.encode()) class ostream: def __lshift__(self, a): sys.stdout.write(str(a)) return self sys.stdout, cout = FastO(), ostream() numbers, num, sign = [], 0, 1 for char in os.read(0, os.fstat(0).st_size): if char >= 48: num = num * 10 + char - 48 elif char == 45: sign = -1 elif char != 13: numbers.append(sign*num) num, sign = 0, 1 if char >= 48: numbers.append(sign*num) getnum = numbers[::-1].pop def main(): n, m = getnum(), getnum() _dp = [[] for _ in range(n)] for i in range(n): ni = getnum() ai = [getnum() for _ in range(ni)] cumsum = [0] * (ni + 1) for j in range(ni): cumsum[j + 1] = cumsum[j] + ai[j] _dpi = [0] * (ni + 1) for j in range(ni + 1): for k in range(j, ni + 1): _dpi[ni + j - k] = max(_dpi[ni + j - k], cumsum[j] + cumsum[-1] - cumsum[k]) _dp[i] = _dpi dp = [0] * (m + 1) for i in range(n): _dpi = _dp[i] for j in reversed(range(m + 1)): dpj = dp[j] for k in range(min(len(_dp[i]), j + 1)): dpj = max(dpj, _dpi[k] + dp[j - k]) dp[j] = dpj cout << dp[m] if __name__ == '__main__': main() ```
output
1
1,876
14
3,753
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. One fine October day a mathematics teacher Vasily Petrov went to a class and saw there n pupils who sat at the <image> desks, two people at each desk. Vasily quickly realized that number n is even. Like all true mathematicians, Vasily has all students numbered from 1 to n. But Vasily Petrov did not like the way the children were seated at the desks. According to him, the students whose numbers differ by 1, can not sit together, as they talk to each other all the time, distract others and misbehave. On the other hand, if a righthanded student sits at the left end of the desk and a lefthanded student sits at the right end of the desk, they hit elbows all the time and distract each other. In other cases, the students who sit at the same desk, do not interfere with each other. Vasily knows very well which students are lefthanders and which ones are righthanders, and he asks you to come up with any order that meets these two uncomplicated conditions (students do not talk to each other and do not bump their elbows). It is guaranteed that the input is such that at least one way to seat the students always exists. Input The first input line contains a single even integer n (4 ≀ n ≀ 100) β€” the number of students in the class. The second line contains exactly n capital English letters "L" and "R". If the i-th letter at the second line equals "L", then the student number i is a lefthander, otherwise he is a righthander. Output Print <image> integer pairs, one pair per line. In the i-th line print the numbers of students that will sit at the i-th desk. The first number in the pair stands for the student who is sitting to the left, and the second number stands for the student who is sitting to the right. Separate the numbers in the pairs by spaces. If there are multiple solutions, print any of them. Examples Input 6 LLRLLL Output 1 4 2 5 6 3 Input 4 RRLL Output 3 1 4 2 Submitted Solution: ``` def main(): with open('input.txt', 'r') as f: n, s = int(f.readline()), f.readline() with open('output.txt', 'w') as f: for i in range(0, n, 2): j = i + n // 2 if s[i] == 'R' and s[j] == 'L': i, j = j, i f.write("%d %d\n" % (i + 1, j + 1)) if __name__ == '__main__': main() ```
instruction
0
1,914
14
3,828
No
output
1
1,914
14
3,829
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. One fine October day a mathematics teacher Vasily Petrov went to a class and saw there n pupils who sat at the <image> desks, two people at each desk. Vasily quickly realized that number n is even. Like all true mathematicians, Vasily has all students numbered from 1 to n. But Vasily Petrov did not like the way the children were seated at the desks. According to him, the students whose numbers differ by 1, can not sit together, as they talk to each other all the time, distract others and misbehave. On the other hand, if a righthanded student sits at the left end of the desk and a lefthanded student sits at the right end of the desk, they hit elbows all the time and distract each other. In other cases, the students who sit at the same desk, do not interfere with each other. Vasily knows very well which students are lefthanders and which ones are righthanders, and he asks you to come up with any order that meets these two uncomplicated conditions (students do not talk to each other and do not bump their elbows). It is guaranteed that the input is such that at least one way to seat the students always exists. Input The first input line contains a single even integer n (4 ≀ n ≀ 100) β€” the number of students in the class. The second line contains exactly n capital English letters "L" and "R". If the i-th letter at the second line equals "L", then the student number i is a lefthander, otherwise he is a righthander. Output Print <image> integer pairs, one pair per line. In the i-th line print the numbers of students that will sit at the i-th desk. The first number in the pair stands for the student who is sitting to the left, and the second number stands for the student who is sitting to the right. Separate the numbers in the pairs by spaces. If there are multiple solutions, print any of them. Examples Input 6 LLRLLL Output 1 4 2 5 6 3 Input 4 RRLL Output 3 1 4 2 Submitted Solution: ``` i,o=open("input.txt","r"),open("output.txt","w") n,a=int(i.readline().strip()),i.readline().strip() for i in range(n-2) : if a[i] == 'L' : o.write(str(i+1)+" "+str(i+3)+"\n") else : o.write(str(i+3)+" "+str(i+1)+"\n") ```
instruction
0
1,915
14
3,830
No
output
1
1,915
14
3,831
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. One fine October day a mathematics teacher Vasily Petrov went to a class and saw there n pupils who sat at the <image> desks, two people at each desk. Vasily quickly realized that number n is even. Like all true mathematicians, Vasily has all students numbered from 1 to n. But Vasily Petrov did not like the way the children were seated at the desks. According to him, the students whose numbers differ by 1, can not sit together, as they talk to each other all the time, distract others and misbehave. On the other hand, if a righthanded student sits at the left end of the desk and a lefthanded student sits at the right end of the desk, they hit elbows all the time and distract each other. In other cases, the students who sit at the same desk, do not interfere with each other. Vasily knows very well which students are lefthanders and which ones are righthanders, and he asks you to come up with any order that meets these two uncomplicated conditions (students do not talk to each other and do not bump their elbows). It is guaranteed that the input is such that at least one way to seat the students always exists. Input The first input line contains a single even integer n (4 ≀ n ≀ 100) β€” the number of students in the class. The second line contains exactly n capital English letters "L" and "R". If the i-th letter at the second line equals "L", then the student number i is a lefthander, otherwise he is a righthander. Output Print <image> integer pairs, one pair per line. In the i-th line print the numbers of students that will sit at the i-th desk. The first number in the pair stands for the student who is sitting to the left, and the second number stands for the student who is sitting to the right. Separate the numbers in the pairs by spaces. If there are multiple solutions, print any of them. Examples Input 6 LLRLLL Output 1 4 2 5 6 3 Input 4 RRLL Output 3 1 4 2 Submitted Solution: ``` #import math #n, m = input().split() #n = int (n) #m = int (m) #n, m, k , l= input().split() #n = int (n) #m = int (m) #k = int (k) #l = int(l) #n = int(input()) #m = int(input()) #s = input() ##t = input() #a = list(map(char, input().split())) #a.append('.') #print(l) #c = list(map(int, input().split())) #c = sorted(c) #x1, y1, x2, y2 =map(int,input().split()) #n = int(input()) #f = [] #t = [0]*n #f = [(int(s1[0]),s1[1]), (int(s2[0]),s2[1]), (int(s3[0]), s3[1])] #f1 = sorted(t, key = lambda tup: tup[0]) inp=open("input.txt","r") out = open("output.txt","w") n = int(inp.readline()) s = inp.readline() l = 0 r = 0 sitz = [0] * n for i in range (n): if(s[i] == 'R' and r < n/2): sitz[r*2+1] = i r += 1 elif (s[i] == 'R'): sitz[l*2] = i l += 1 elif(s[i] == 'L' and l < n/2): sitz[l*2] = i l += 1 elif (s[i] == 'L'): sitz[r*2+1] = i r += 1 for i in range(0,n, 2): out.write(str(sitz[i]+1) + " "+ str(sitz[i+1]+1)+ "\n") out.close() inp.close() ```
instruction
0
1,916
14
3,832
No
output
1
1,916
14
3,833
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. One fine October day a mathematics teacher Vasily Petrov went to a class and saw there n pupils who sat at the <image> desks, two people at each desk. Vasily quickly realized that number n is even. Like all true mathematicians, Vasily has all students numbered from 1 to n. But Vasily Petrov did not like the way the children were seated at the desks. According to him, the students whose numbers differ by 1, can not sit together, as they talk to each other all the time, distract others and misbehave. On the other hand, if a righthanded student sits at the left end of the desk and a lefthanded student sits at the right end of the desk, they hit elbows all the time and distract each other. In other cases, the students who sit at the same desk, do not interfere with each other. Vasily knows very well which students are lefthanders and which ones are righthanders, and he asks you to come up with any order that meets these two uncomplicated conditions (students do not talk to each other and do not bump their elbows). It is guaranteed that the input is such that at least one way to seat the students always exists. Input The first input line contains a single even integer n (4 ≀ n ≀ 100) β€” the number of students in the class. The second line contains exactly n capital English letters "L" and "R". If the i-th letter at the second line equals "L", then the student number i is a lefthander, otherwise he is a righthander. Output Print <image> integer pairs, one pair per line. In the i-th line print the numbers of students that will sit at the i-th desk. The first number in the pair stands for the student who is sitting to the left, and the second number stands for the student who is sitting to the right. Separate the numbers in the pairs by spaces. If there are multiple solutions, print any of them. Examples Input 6 LLRLLL Output 1 4 2 5 6 3 Input 4 RRLL Output 3 1 4 2 Submitted Solution: ``` #import math #n, m = input().split() #n = int (n) #m = int (m) #n, m, k , l= input().split() #n = int (n) #m = int (m) #k = int (k) #l = int(l) #n = int(input()) #m = int(input()) #s = input() ##t = input() #a = list(map(char, input().split())) #a.append('.') #print(l) #c = list(map(int, input().split())) #c = sorted(c) #x1, y1, x2, y2 =map(int,input().split()) #n = int(input()) #f = [] #t = [0]*n #f = [(int(s1[0]),s1[1]), (int(s2[0]),s2[1]), (int(s3[0]), s3[1])] #f1 = sorted(t, key = lambda tup: tup[0]) inp=open("input.txt","r") out = open("output.txt","w") n = int(inp.readline()) s = inp.readline() l = 0 r = 0 sitz = [0] * n for i in range (n): if l < n/2: sitz[l *2] = i l += 1 else: sitz[r*2+1] = i r += 1 for i in range(0,n, 2): if (s[sitz[i] == 'L' and s[sitz[i+1]] == 'R']): sitz[i], sitz[i+1] = sitz[i+1], sitz[i] out.write(str(sitz[i]+1) + " "+ str(sitz[i+1]+1)+ "\n") out.close() inp.close() ```
instruction
0
1,917
14
3,834
No
output
1
1,917
14
3,835
Provide tags and a correct Python 3 solution for this coding contest problem. Little Robber Girl likes to scare animals in her zoo for fun. She decided to arrange the animals in a row in the order of non-decreasing height. However, the animals were so scared that they couldn't stay in the right places. The robber girl was angry at first, but then she decided to arrange the animals herself. She repeatedly names numbers l and r such that r - l + 1 is even. After that animals that occupy positions between l and r inclusively are rearranged as follows: the animal at position l swaps places with the animal at position l + 1, the animal l + 2 swaps with the animal l + 3, ..., finally, the animal at position r - 1 swaps with the animal r. Help the robber girl to arrange the animals in the order of non-decreasing height. You should name at most 20 000 segments, since otherwise the robber girl will become bored and will start scaring the animals again. Input The first line contains a single integer n (1 ≀ n ≀ 100) β€” number of animals in the robber girl's zoo. The second line contains n space-separated integers a1, a2, ..., an (1 ≀ ai ≀ 109), where ai is the height of the animal occupying the i-th place. Output Print the sequence of operations that will rearrange the animals by non-decreasing height. The output should contain several lines, i-th of the lines should contain two space-separated integers li and ri (1 ≀ li < ri ≀ n) β€” descriptions of segments the robber girl should name. The segments should be described in the order the operations are performed. The number of operations should not exceed 20 000. If the animals are arranged correctly from the start, you are allowed to output nothing. Examples Input 4 2 1 4 3 Output 1 4 Input 7 36 28 57 39 66 69 68 Output 1 4 6 7 Input 5 1 2 1 2 1 Output 2 5 3 4 1 4 1 4 Note Note that you don't have to minimize the number of operations. Any solution that performs at most 20 000 operations is allowed.
instruction
0
2,098
14
4,196
Tags: constructive algorithms, implementation, sortings Correct Solution: ``` def zoo(lst): result = list() for i in range(len(lst) + 2): for j in range(len(lst) - 1): if lst[j] > lst[j + 1]: result.append([j + 1, j + 2]) lst[j], lst[j + 1] = lst[j + 1], lst[j] return result n = int(input()) a = [int(x) for x in input().split()] for elem in zoo(a): print(*elem) ```
output
1
2,098
14
4,197
Provide tags and a correct Python 3 solution for this coding contest problem. Hands that shed innocent blood! There are n guilty people in a line, the i-th of them holds a claw with length Li. The bell rings and every person kills some of people in front of him. All people kill others at the same time. Namely, the i-th person kills the j-th person if and only if j < i and j β‰₯ i - Li. You are given lengths of the claws. You need to find the total number of alive people after the bell rings. Input The first line contains one integer n (1 ≀ n ≀ 106) β€” the number of guilty people. Second line contains n space-separated integers L1, L2, ..., Ln (0 ≀ Li ≀ 109), where Li is the length of the i-th person's claw. Output Print one integer β€” the total number of alive people after the bell rings. Examples Input 4 0 1 0 10 Output 1 Input 2 0 0 Output 2 Input 10 1 1 3 0 0 0 2 1 0 3 Output 3 Note In first sample the last person kills everyone in front of him.
instruction
0
2,167
14
4,334
Tags: greedy, implementation, two pointers Correct Solution: ``` n = int(input()) l = [int(x) for x in input().split()] max_claw = 0 alive_count = 1 for i in range(n-1, -1, -1): max_claw = max(max_claw, l[i]) if max_claw == 0 and i > 0: alive_count += 1 else: max_claw -= 1 print(alive_count) ```
output
1
2,167
14
4,335
Provide tags and a correct Python 3 solution for this coding contest problem. Hands that shed innocent blood! There are n guilty people in a line, the i-th of them holds a claw with length Li. The bell rings and every person kills some of people in front of him. All people kill others at the same time. Namely, the i-th person kills the j-th person if and only if j < i and j β‰₯ i - Li. You are given lengths of the claws. You need to find the total number of alive people after the bell rings. Input The first line contains one integer n (1 ≀ n ≀ 106) β€” the number of guilty people. Second line contains n space-separated integers L1, L2, ..., Ln (0 ≀ Li ≀ 109), where Li is the length of the i-th person's claw. Output Print one integer β€” the total number of alive people after the bell rings. Examples Input 4 0 1 0 10 Output 1 Input 2 0 0 Output 2 Input 10 1 1 3 0 0 0 2 1 0 3 Output 3 Note In first sample the last person kills everyone in front of him.
instruction
0
2,168
14
4,336
Tags: greedy, implementation, two pointers Correct Solution: ``` n = int(input()) a = list(map(int, input().split())) kill = 0 minus = 0 s = [] for i in range(n - 1, -1, -1): if kill > 0: kill -= 1; minus += 1; kill = max(kill, a[i]) print(n - minus) ```
output
1
2,168
14
4,337
Provide tags and a correct Python 3 solution for this coding contest problem. Hands that shed innocent blood! There are n guilty people in a line, the i-th of them holds a claw with length Li. The bell rings and every person kills some of people in front of him. All people kill others at the same time. Namely, the i-th person kills the j-th person if and only if j < i and j β‰₯ i - Li. You are given lengths of the claws. You need to find the total number of alive people after the bell rings. Input The first line contains one integer n (1 ≀ n ≀ 106) β€” the number of guilty people. Second line contains n space-separated integers L1, L2, ..., Ln (0 ≀ Li ≀ 109), where Li is the length of the i-th person's claw. Output Print one integer β€” the total number of alive people after the bell rings. Examples Input 4 0 1 0 10 Output 1 Input 2 0 0 Output 2 Input 10 1 1 3 0 0 0 2 1 0 3 Output 3 Note In first sample the last person kills everyone in front of him.
instruction
0
2,169
14
4,338
Tags: greedy, implementation, two pointers Correct Solution: ``` if __name__ == "__main__": n = int(input()) t = list(map(int, input().split())) a = [0] * n for i in range(n): a[max(0, i - t[i])] += 1 a[i] -= 1 res = 0 for i in range(n): if i > 0: a[i] += a[i - 1] if a[i] == 0: res += 1 print(res) ```
output
1
2,169
14
4,339
Provide tags and a correct Python 3 solution for this coding contest problem. Hands that shed innocent blood! There are n guilty people in a line, the i-th of them holds a claw with length Li. The bell rings and every person kills some of people in front of him. All people kill others at the same time. Namely, the i-th person kills the j-th person if and only if j < i and j β‰₯ i - Li. You are given lengths of the claws. You need to find the total number of alive people after the bell rings. Input The first line contains one integer n (1 ≀ n ≀ 106) β€” the number of guilty people. Second line contains n space-separated integers L1, L2, ..., Ln (0 ≀ Li ≀ 109), where Li is the length of the i-th person's claw. Output Print one integer β€” the total number of alive people after the bell rings. Examples Input 4 0 1 0 10 Output 1 Input 2 0 0 Output 2 Input 10 1 1 3 0 0 0 2 1 0 3 Output 3 Note In first sample the last person kills everyone in front of him.
instruction
0
2,170
14
4,340
Tags: greedy, implementation, two pointers Correct Solution: ``` q=int(input()) a=list(map(int,input().split())) ans=0 t=q for i in range(q-1,-1,-1): if t>i: ans+=1 t=min(t,i-a[i]) print(ans) ```
output
1
2,170
14
4,341
Provide tags and a correct Python 3 solution for this coding contest problem. Hands that shed innocent blood! There are n guilty people in a line, the i-th of them holds a claw with length Li. The bell rings and every person kills some of people in front of him. All people kill others at the same time. Namely, the i-th person kills the j-th person if and only if j < i and j β‰₯ i - Li. You are given lengths of the claws. You need to find the total number of alive people after the bell rings. Input The first line contains one integer n (1 ≀ n ≀ 106) β€” the number of guilty people. Second line contains n space-separated integers L1, L2, ..., Ln (0 ≀ Li ≀ 109), where Li is the length of the i-th person's claw. Output Print one integer β€” the total number of alive people after the bell rings. Examples Input 4 0 1 0 10 Output 1 Input 2 0 0 Output 2 Input 10 1 1 3 0 0 0 2 1 0 3 Output 3 Note In first sample the last person kills everyone in front of him.
instruction
0
2,171
14
4,342
Tags: greedy, implementation, two pointers Correct Solution: ``` n = int(input()) claws = list(map(int, input().split())) c = 0 r = n for claw in reversed(claws): if c > 0: r -= 1 c = max(c - 1, claw) print(r) ```
output
1
2,171
14
4,343
Provide tags and a correct Python 3 solution for this coding contest problem. Hands that shed innocent blood! There are n guilty people in a line, the i-th of them holds a claw with length Li. The bell rings and every person kills some of people in front of him. All people kill others at the same time. Namely, the i-th person kills the j-th person if and only if j < i and j β‰₯ i - Li. You are given lengths of the claws. You need to find the total number of alive people after the bell rings. Input The first line contains one integer n (1 ≀ n ≀ 106) β€” the number of guilty people. Second line contains n space-separated integers L1, L2, ..., Ln (0 ≀ Li ≀ 109), where Li is the length of the i-th person's claw. Output Print one integer β€” the total number of alive people after the bell rings. Examples Input 4 0 1 0 10 Output 1 Input 2 0 0 Output 2 Input 10 1 1 3 0 0 0 2 1 0 3 Output 3 Note In first sample the last person kills everyone in front of him.
instruction
0
2,172
14
4,344
Tags: greedy, implementation, two pointers Correct Solution: ``` #10 #1 1 3 0 0 0 2 1 0 3 n = int(input()) lv = list(map(int,input().strip().split(' '))) ans = 0 safe = n i = n while i > 0: if i <= safe: ans += 1 safe = min(safe,i - lv[i-1] - 1) if safe < 0: break i -= 1 print(ans) ```
output
1
2,172
14
4,345
Provide tags and a correct Python 3 solution for this coding contest problem. Hands that shed innocent blood! There are n guilty people in a line, the i-th of them holds a claw with length Li. The bell rings and every person kills some of people in front of him. All people kill others at the same time. Namely, the i-th person kills the j-th person if and only if j < i and j β‰₯ i - Li. You are given lengths of the claws. You need to find the total number of alive people after the bell rings. Input The first line contains one integer n (1 ≀ n ≀ 106) β€” the number of guilty people. Second line contains n space-separated integers L1, L2, ..., Ln (0 ≀ Li ≀ 109), where Li is the length of the i-th person's claw. Output Print one integer β€” the total number of alive people after the bell rings. Examples Input 4 0 1 0 10 Output 1 Input 2 0 0 Output 2 Input 10 1 1 3 0 0 0 2 1 0 3 Output 3 Note In first sample the last person kills everyone in front of him.
instruction
0
2,173
14
4,346
Tags: greedy, implementation, two pointers Correct Solution: ``` #Wrath n = int(input()) l = list(map(int, input().split())) i = n - 1 j = n - 1 count = 0 while j >= 0 and i >= 0: if j >= i: count += 1 j = i - l[i] - 1 if i - l[i] <= j: j = i - l[i] - 1 i -= 1 print(count) ```
output
1
2,173
14
4,347
Provide tags and a correct Python 3 solution for this coding contest problem. Hands that shed innocent blood! There are n guilty people in a line, the i-th of them holds a claw with length Li. The bell rings and every person kills some of people in front of him. All people kill others at the same time. Namely, the i-th person kills the j-th person if and only if j < i and j β‰₯ i - Li. You are given lengths of the claws. You need to find the total number of alive people after the bell rings. Input The first line contains one integer n (1 ≀ n ≀ 106) β€” the number of guilty people. Second line contains n space-separated integers L1, L2, ..., Ln (0 ≀ Li ≀ 109), where Li is the length of the i-th person's claw. Output Print one integer β€” the total number of alive people after the bell rings. Examples Input 4 0 1 0 10 Output 1 Input 2 0 0 Output 2 Input 10 1 1 3 0 0 0 2 1 0 3 Output 3 Note In first sample the last person kills everyone in front of him.
instruction
0
2,174
14
4,348
Tags: greedy, implementation, two pointers Correct Solution: ``` n = int(input()) l = list(map(int, input().split())) left = n - 1 right = n - 1 ans = 0 for i in range(n-1, -1, -1): right = i if left == right: ans += 1 left = min(left, right - l[i] - 1) print(ans) ```
output
1
2,174
14
4,349
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Hands that shed innocent blood! There are n guilty people in a line, the i-th of them holds a claw with length Li. The bell rings and every person kills some of people in front of him. All people kill others at the same time. Namely, the i-th person kills the j-th person if and only if j < i and j β‰₯ i - Li. You are given lengths of the claws. You need to find the total number of alive people after the bell rings. Input The first line contains one integer n (1 ≀ n ≀ 106) β€” the number of guilty people. Second line contains n space-separated integers L1, L2, ..., Ln (0 ≀ Li ≀ 109), where Li is the length of the i-th person's claw. Output Print one integer β€” the total number of alive people after the bell rings. Examples Input 4 0 1 0 10 Output 1 Input 2 0 0 Output 2 Input 10 1 1 3 0 0 0 2 1 0 3 Output 3 Note In first sample the last person kills everyone in front of him. Submitted Solution: ``` n = int(input()) l = list(map(int,input().split())) s = set() i = len(l)-1 j = len(l)-2 while(i > -1): while(j > -1 and i > j): if (j+1) >= ((i+1)-l[i]): #print(i,j) s.add(j) j = j-1 else: break if i == j: j = j-1 else: i = i-1 print(len(l)-len(s)) ```
instruction
0
2,175
14
4,350
Yes
output
1
2,175
14
4,351
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Hands that shed innocent blood! There are n guilty people in a line, the i-th of them holds a claw with length Li. The bell rings and every person kills some of people in front of him. All people kill others at the same time. Namely, the i-th person kills the j-th person if and only if j < i and j β‰₯ i - Li. You are given lengths of the claws. You need to find the total number of alive people after the bell rings. Input The first line contains one integer n (1 ≀ n ≀ 106) β€” the number of guilty people. Second line contains n space-separated integers L1, L2, ..., Ln (0 ≀ Li ≀ 109), where Li is the length of the i-th person's claw. Output Print one integer β€” the total number of alive people after the bell rings. Examples Input 4 0 1 0 10 Output 1 Input 2 0 0 Output 2 Input 10 1 1 3 0 0 0 2 1 0 3 Output 3 Note In first sample the last person kills everyone in front of him. Submitted Solution: ``` def solve(n,seq) : alive = n pointer = n-1 alivePointer = n-2 while pointer > 0 and alivePointer >= 0 : value = (pointer+1) - seq[pointer] if value <= 0 : value = 1 value -= 1 if alivePointer == pointer : alivePointer -= 1 if alivePointer >= value : diff = alivePointer - value + 1 alivePointer = value - 1 alive -= diff pointer -= 1 return alive n = int(input()) seq = list(map(int,input().split())) print (solve(n,seq)) ```
instruction
0
2,176
14
4,352
Yes
output
1
2,176
14
4,353
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Hands that shed innocent blood! There are n guilty people in a line, the i-th of them holds a claw with length Li. The bell rings and every person kills some of people in front of him. All people kill others at the same time. Namely, the i-th person kills the j-th person if and only if j < i and j β‰₯ i - Li. You are given lengths of the claws. You need to find the total number of alive people after the bell rings. Input The first line contains one integer n (1 ≀ n ≀ 106) β€” the number of guilty people. Second line contains n space-separated integers L1, L2, ..., Ln (0 ≀ Li ≀ 109), where Li is the length of the i-th person's claw. Output Print one integer β€” the total number of alive people after the bell rings. Examples Input 4 0 1 0 10 Output 1 Input 2 0 0 Output 2 Input 10 1 1 3 0 0 0 2 1 0 3 Output 3 Note In first sample the last person kills everyone in front of him. Submitted Solution: ``` n = int(input()) L = [int(i) for i in input().split()] pomoika = 0 l = n for i in range(n - 1, 0, -1): nl = max(i - L[i], 0) if l > nl: if i < l: pomoika += i - nl else: pomoika += l - nl l = nl if l <= 0: break print(n - pomoika) ```
instruction
0
2,177
14
4,354
Yes
output
1
2,177
14
4,355
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Hands that shed innocent blood! There are n guilty people in a line, the i-th of them holds a claw with length Li. The bell rings and every person kills some of people in front of him. All people kill others at the same time. Namely, the i-th person kills the j-th person if and only if j < i and j β‰₯ i - Li. You are given lengths of the claws. You need to find the total number of alive people after the bell rings. Input The first line contains one integer n (1 ≀ n ≀ 106) β€” the number of guilty people. Second line contains n space-separated integers L1, L2, ..., Ln (0 ≀ Li ≀ 109), where Li is the length of the i-th person's claw. Output Print one integer β€” the total number of alive people after the bell rings. Examples Input 4 0 1 0 10 Output 1 Input 2 0 0 Output 2 Input 10 1 1 3 0 0 0 2 1 0 3 Output 3 Note In first sample the last person kills everyone in front of him. Submitted Solution: ``` n = int(input()) a = [i - int(x) + 1 for i, x in enumerate(input().split())] a.insert(0, 0) min_a = a[-1] res = n for i in range(n - 1, 0, -1): if i >= min_a: res -= 1 min_a = min(min_a, a[i]) print(res) ```
instruction
0
2,178
14
4,356
Yes
output
1
2,178
14
4,357
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Hands that shed innocent blood! There are n guilty people in a line, the i-th of them holds a claw with length Li. The bell rings and every person kills some of people in front of him. All people kill others at the same time. Namely, the i-th person kills the j-th person if and only if j < i and j β‰₯ i - Li. You are given lengths of the claws. You need to find the total number of alive people after the bell rings. Input The first line contains one integer n (1 ≀ n ≀ 106) β€” the number of guilty people. Second line contains n space-separated integers L1, L2, ..., Ln (0 ≀ Li ≀ 109), where Li is the length of the i-th person's claw. Output Print one integer β€” the total number of alive people after the bell rings. Examples Input 4 0 1 0 10 Output 1 Input 2 0 0 Output 2 Input 10 1 1 3 0 0 0 2 1 0 3 Output 3 Note In first sample the last person kills everyone in front of him. Submitted Solution: ``` n=int(input()) l=input().split() count=1 var=0 j=1 while j<n: if l[n-j]=='0': count+=1 j+=1 else: j=j+int(l[n-j]) print(count) ```
instruction
0
2,179
14
4,358
No
output
1
2,179
14
4,359
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Hands that shed innocent blood! There are n guilty people in a line, the i-th of them holds a claw with length Li. The bell rings and every person kills some of people in front of him. All people kill others at the same time. Namely, the i-th person kills the j-th person if and only if j < i and j β‰₯ i - Li. You are given lengths of the claws. You need to find the total number of alive people after the bell rings. Input The first line contains one integer n (1 ≀ n ≀ 106) β€” the number of guilty people. Second line contains n space-separated integers L1, L2, ..., Ln (0 ≀ Li ≀ 109), where Li is the length of the i-th person's claw. Output Print one integer β€” the total number of alive people after the bell rings. Examples Input 4 0 1 0 10 Output 1 Input 2 0 0 Output 2 Input 10 1 1 3 0 0 0 2 1 0 3 Output 3 Note In first sample the last person kills everyone in front of him. Submitted Solution: ``` n=int(input()) m=list(map(int,input().split())) c=set() x=1 for i in range(len(m)): x-=1 for j in range(1,min(i,m[i]-x)+1): c.add(i-j) x=max(x,m[i],1) print(n-len(c)) ```
instruction
0
2,180
14
4,360
No
output
1
2,180
14
4,361
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Hands that shed innocent blood! There are n guilty people in a line, the i-th of them holds a claw with length Li. The bell rings and every person kills some of people in front of him. All people kill others at the same time. Namely, the i-th person kills the j-th person if and only if j < i and j β‰₯ i - Li. You are given lengths of the claws. You need to find the total number of alive people after the bell rings. Input The first line contains one integer n (1 ≀ n ≀ 106) β€” the number of guilty people. Second line contains n space-separated integers L1, L2, ..., Ln (0 ≀ Li ≀ 109), where Li is the length of the i-th person's claw. Output Print one integer β€” the total number of alive people after the bell rings. Examples Input 4 0 1 0 10 Output 1 Input 2 0 0 Output 2 Input 10 1 1 3 0 0 0 2 1 0 3 Output 3 Note In first sample the last person kills everyone in front of him. Submitted Solution: ``` size = int(input()) array = [int(i) for i in input().split()] check = [0]*size total = 0 for i in range(size-1,0,-1): if array[i]: val = i - array[i] if 0 < i - array[i] else 0 check[val] = 1 pos = size -1 for i in range(size-1,-1,-1): if check[i]: total += pos - i for j in range(i,-1,-1): if array[j]: pos = j break print(size-total) ```
instruction
0
2,181
14
4,362
No
output
1
2,181
14
4,363
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response. Hands that shed innocent blood! There are n guilty people in a line, the i-th of them holds a claw with length Li. The bell rings and every person kills some of people in front of him. All people kill others at the same time. Namely, the i-th person kills the j-th person if and only if j < i and j β‰₯ i - Li. You are given lengths of the claws. You need to find the total number of alive people after the bell rings. Input The first line contains one integer n (1 ≀ n ≀ 106) β€” the number of guilty people. Second line contains n space-separated integers L1, L2, ..., Ln (0 ≀ Li ≀ 109), where Li is the length of the i-th person's claw. Output Print one integer β€” the total number of alive people after the bell rings. Examples Input 4 0 1 0 10 Output 1 Input 2 0 0 Output 2 Input 10 1 1 3 0 0 0 2 1 0 3 Output 3 Note In first sample the last person kills everyone in front of him. Submitted Solution: ``` n=int(input()) claw=[int(x) for x in input().split()] kill=[0]*n for i in range(n-2,-1,-1): kill[i]=claw[i+1]+max(kill[i+1]-1,0) alive=0 for i in range(n): if kill[i]<2: alive+=1 print(alive) ```
instruction
0
2,182
14
4,364
No
output
1
2,182
14
4,365
Provide a correct Python 3 solution for this coding contest problem. Joisino is working as a receptionist at a theater. The theater has 100000 seats, numbered from 1 to 100000. According to her memo, N groups of audiences have come so far, and the i-th group occupies the consecutive seats from Seat l_i to Seat r_i (inclusive). How many people are sitting at the theater now? Constraints * 1≀N≀1000 * 1≀l_i≀r_i≀100000 * No seat is occupied by more than one person. * All input values are integers. Input Input is given from Standard Input in the following format: N l_1 r_1 : l_N r_N Output Print the number of people sitting at the theater. Examples Input 1 24 30 Output 7 Input 2 6 8 3 3 Output 4
instruction
0
2,319
14
4,638
"Correct Solution: ``` n = int(input()) cnt = 0 for i in range(n): l,r = map(int,input().split());cnt += r-l+1 print(cnt) ```
output
1
2,319
14
4,639
Provide a correct Python 3 solution for this coding contest problem. Joisino is working as a receptionist at a theater. The theater has 100000 seats, numbered from 1 to 100000. According to her memo, N groups of audiences have come so far, and the i-th group occupies the consecutive seats from Seat l_i to Seat r_i (inclusive). How many people are sitting at the theater now? Constraints * 1≀N≀1000 * 1≀l_i≀r_i≀100000 * No seat is occupied by more than one person. * All input values are integers. Input Input is given from Standard Input in the following format: N l_1 r_1 : l_N r_N Output Print the number of people sitting at the theater. Examples Input 1 24 30 Output 7 Input 2 6 8 3 3 Output 4
instruction
0
2,320
14
4,640
"Correct Solution: ``` N=int(input()) ans=0 for i in range(N): l,r=map(int,input().split()) ans+=abs(l-r)+1 print(ans) ```
output
1
2,320
14
4,641