#_*_coding:utf_8_ import sys import os class Graph():     def __init__(self, V, E):         self.V = V         self.E = E         self.visited = []         self.dict = {}         self.fd = open("input.txt")     def initGraph(self):         self.visited = [0 for i in range(self.V+1)]         for i in range(self.E):             f, t = map(int, self.fd.readline().split())             #f, t = map(int, sys.stdin.readline().split())             if self.dict.has_key(f)==False:                 l = []                 l.append(t)                 self.dict[f] = l             else:                 l = self.dict[f]                 l.append(t)                 self.dict[f] = l         def dfsGraph(self, src):         self.visited[src] = 1         print src ,         if self.dict.get(src): #self.dict[src]会出现异常             for u in self.dict[src]:                 if self.visited[u]==0:                     self.dfsGraph(u) graph = Graph(6, 10) graph.initGraph() graph.dfsGraph(1)

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