import sys sys.setrecursionlimit(300000) def dfs(graph, v, visited, k, a): visited[v] = True for i in graph[v]: if not visited[i]: dfs(graph, i, visited, k, a) a[v] += a[i] k[0] += abs(a[i]) a[i] = 0 def solution(a, edges): answer = 0 sum = 0 for i in a: # 판별 sum += i if sum != 0: # 판별하여 끝내기 answer = -1 return answer graph = [[] for i in range(len(a))] for i in edges: graph[i[0]].append(i[1]) graph[i[1]].append(i[0]) visited = [False] * len(graph) k = [0] dfs(graph, 1, visited, k, a) answer = k[0] return answer