帖子import math

import math from collections import defaultdict, deque def is_perfect_square(x): root = int(math.isqrt(x)) return root * root == x def solve(n, val, edge): tree = defaultdict(list) for u, v in edge: tree[u].append(v) tree[v].append(u) parent = [-1] * n path = [[] for _ in range(n)] queue = deque([0]) visited = [False] * n visited[0] = True while queue: node = queue.popleft() for neighbor in tree[node]: if not visited[neighbor]: visited[neighbor] = True parent[neighbor] = node path[neighbor] = path[node] + [node] queue.append(neighbor) total_sum = 0 for i in range(1, n): vi = 0 for anc in path[i]: if is_perfect_square(val[i] * val[anc]): vi += 1 total_sum += vi return total_sum n=int(input()) val=[int(i) for i in input().split()] edge=[[int(i) for i in input().split()] for _ in range(n-1)] print(solve(n,val,edge)) Tree Climber✅✅