[DFS][Python]Finding Path from start to goal in graph 

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def dfs(graph, start):
    visited, stack = [], [start]
    while stack:
        vertex = stack.pop()
        if vertex not in visited:
            visited.append(vertex)
            stack += graph[vertex] - set(visited)
    return visited

for t in range(int(input())):
    graph = dict()
    v, e = list(map(int, input().split()))

    # Graph initialize
    for i in range(v):
        graph[str(i+1)] = set()

    # Links allocated by input value
    for _ in range(e):
        key, val = input().split()
        graph[key].add(val)

    s, g = input().split()
    vtd = dfs(graph, s)

    if g in vtd:
        result = 1
    else:
        result = 0

    print("#{} {}".format(t+1, result))
참고문제: SW Expert Academy 4871번 문제

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  1. q2019년 2월 7일 오전 10:03

    reference
    http://ejklike.github.io/2018/01/05/bfs-and-dfs.html
    https://eddmann.com/posts/depth-first-search-and-breadth-first-search-in-python/

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