def BFS(garph,s):
    '''

    :param garph:圖
    :param s: 開始的節點
    :return:
    '''
    queue =[]#存放所有的順序
    queue.append(s)
    seen=set()

    seen.add(s)
    while (len(queue)>0):
        vertex =queue.pop(0)
        nodes = graph[vertex]
        for w in nodes:
            if w not in seen:
                queue.append(w)
                seen.add(w)
        print(vertex)

def
 
 DFS(garph,s):
    '''

    :param garph:圖
    :param s: 開始的節點
    :return:
    '''
    queue =[]#存放所有的順序
    queue.append(s)
    seen=set()

    seen.add(s)
    while (len(queue)>0):
        vertex =queue.pop()
        nodes = graph[vertex]
        for w in nodes:
            if w not in seen:
                queue.append(w)
                seen.add(w)
        print(vertex)
def
 
 findleastroad(graph,s):
    '''

      :param garph:圖
      :param s: 開始的節點
      :return:
      '''
    queue = []  # 存放所有的順序
    queue.append(s)
    seen = set()
    seen.add(s)
    parent={s:None}#s的前一個點是空

    while (len(queue) > 0):
        vertex = queue.pop(0)
        nodes = graph[vertex]
        for
 
 w in nodes:
            if w not in seen:
                queue.append(w)
                seen.add(w)
                parent[w]=vertex
        #print(vertex)
    return parent

if __name__=='__main__':
    graph = {
        # 通過一個點找到所有的相鄰點
        "A": ['B', 'C'],
        "B": ['A', 'C', 'D'],
        "C": ['A', 'B', 'D', 'E'],
        "D": ['B', 'C', 'E', 'F'],
        "E": ['C','D'],
        'F': ['D']
    }
    print('BFS結果：')

    BFS(graph,'A')
    print('DFS結果：')
    DFS(graph,'A')
    print('最短路徑')
    parent=findleastroad(graph,'E')
    for key in parent:
        print(key,parent[key])#打印出每一個節點的前一個點
    v='B'
    while v!=None:
        print(v)
        v=parent[v]