networkx图论Depth First Search深度优先搜索遍历DFS，基于栈，Python

骑猪看日落 2023-10-02 14:18 23阅读 0赞

（1）深度优先搜索遍历，通常使用栈来保存遍历搜索过的节点记录。当搜索到的节点没有子节点，意味着达到了尽头，开始回退。回退的过程其实就是把栈顶的节点弹出（删掉），然后再次在栈中读第一个元素（本例是列表实现的栈，即为0号元素）。

（2）每个节点用一个标志位标记当前节点是否已经访问过，如果访问过，压入栈顶。

（3）每次迭代独取当前顶点V时候，同时要把顶点V的子节点压入栈。

import networkx as nx
    import matplotlib.pyplot as plt
    
    # 记录搜索路径
    search_path = []
    
    
    def my_graph():
        # G = nx.gnm_random_graph(n=6, m=8)
        # G = nx.balanced_tree(r=3, h=2)
        G = nx.random_tree(20)
    
        pos = nx.spring_layout(G)
        nx.draw_networkx(G, pos,
                         node_color='green',
                         node_size=300,
                         font_size=10,
                         font_color='white',
                         edge_color='gray',
                         width=1,
                         with_labels=True)
    
        print('G.nodes(data=True)', G.nodes(data=True))
    
        dfs(G)
    
        plt.show()
    
    
    # 基于栈实深度优先遍历搜索
    def dfs(G):
        for n in G.nodes():
            G.nodes[n]['visited'] = False
        print(G.nodes(data=True))
        print(G.edges(data=True))
    
        V = 0
    
        stack = []  # 用列表当作一个栈，只在栈顶操作（数组的第1个位置）
        stack.append(V)
    
        while True:
            if len(stack) == 0:
                break
    
            print('-----')
            print('stack-', stack)
    
            visit_node = stack[0]
            G.nodes[visit_node]['visited'] = True
            print('访问', visit_node)
    
            neighbors = nx.neighbors(G, visit_node)
    
            count = 0
            for node in neighbors:
                visited = G.nodes[node]['visited']
                if (visited) or (node in stack) or (node in search_path):
                    continue
    
                stack.insert(0, node)
                count = count + 1
    
            print('nodes', G.nodes(data=True))
    
            if count == 0:
                print(visit_node, '走到尽头')
                del (stack[0])
                print('弹出', visit_node)
                search_path.append(visit_node)
    
            print('stack--', stack)
    
        list.reverse(search_path)
        print('search_path', search_path)
    
        print('\n==对比深度搜索遍历结果==')
        print('networkx dfs',list(nx.dfs_tree(G,V)))
    
    
    if __name__ == '__main__':
        my_graph()

生成图：

![watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBAemhhbmdwaGls_size_20_color_FFFFFF_t_70_g_se_x_16][]

日志输出：

G.nodes(data=True) [(0, {}), (1, {}), (2, {}), (3, {}), (4, {}), (5, {}), (6, {}), (7, {}), (8, {}), (9, {}), (10, {}), (11, {}), (12, {}), (13, {}), (14, {}), (15, {}), (16, {}), (17, {}), (18, {}), (19, {})]
    [(0, {'visited': False}), (1, {'visited': False}), (2, {'visited': False}), (3, {'visited': False}), (4, {'visited': False}), (5, {'visited': False}), (6, {'visited': False}), (7, {'visited': False}), (8, {'visited': False}), (9, {'visited': False}), (10, {'visited': False}), (11, {'visited': False}), (12, {'visited': False}), (13, {'visited': False}), (14, {'visited': False}), (15, {'visited': False}), (16, {'visited': False}), (17, {'visited': False}), (18, {'visited': False}), (19, {'visited': False})]
    [(0, 7, {}), (1, 4, {}), (1, 10, {}), (1, 5, {}), (1, 19, {}), (2, 8, {}), (2, 17, {}), (3, 7, {}), (5, 17, {}), (6, 16, {}), (7, 8, {}), (8, 15, {}), (9, 18, {}), (9, 14, {}), (11, 15, {}), (12, 16, {}), (13, 18, {}), (14, 16, {}), (14, 17, {})]
    -----
    stack- [0]
    访问 0
    nodes [(0, {'visited': True}), (1, {'visited': False}), (2, {'visited': False}), (3, {'visited': False}), (4, {'visited': False}), (5, {'visited': False}), (6, {'visited': False}), (7, {'visited': False}), (8, {'visited': False}), (9, {'visited': False}), (10, {'visited': False}), (11, {'visited': False}), (12, {'visited': False}), (13, {'visited': False}), (14, {'visited': False}), (15, {'visited': False}), (16, {'visited': False}), (17, {'visited': False}), (18, {'visited': False}), (19, {'visited': False})]
    stack-- [7, 0]
    -----
    stack- [7, 0]
    访问 7
    nodes [(0, {'visited': True}), (1, {'visited': False}), (2, {'visited': False}), (3, {'visited': False}), (4, {'visited': False}), (5, {'visited': False}), (6, {'visited': False}), (7, {'visited': True}), (8, {'visited': False}), (9, {'visited': False}), (10, {'visited': False}), (11, {'visited': False}), (12, {'visited': False}), (13, {'visited': False}), (14, {'visited': False}), (15, {'visited': False}), (16, {'visited': False}), (17, {'visited': False}), (18, {'visited': False}), (19, {'visited': False})]
    stack-- [8, 3, 7, 0]
    -----
    stack- [8, 3, 7, 0]
    访问 8
    nodes [(0, {'visited': True}), (1, {'visited': False}), (2, {'visited': False}), (3, {'visited': False}), (4, {'visited': False}), (5, {'visited': False}), (6, {'visited': False}), (7, {'visited': True}), (8, {'visited': True}), (9, {'visited': False}), (10, {'visited': False}), (11, {'visited': False}), (12, {'visited': False}), (13, {'visited': False}), (14, {'visited': False}), (15, {'visited': False}), (16, {'visited': False}), (17, {'visited': False}), (18, {'visited': False}), (19, {'visited': False})]
    stack-- [2, 15, 8, 3, 7, 0]
    -----
    stack- [2, 15, 8, 3, 7, 0]
    访问 2
    nodes [(0, {'visited': True}), (1, {'visited': False}), (2, {'visited': True}), (3, {'visited': False}), (4, {'visited': False}), (5, {'visited': False}), (6, {'visited': False}), (7, {'visited': True}), (8, {'visited': True}), (9, {'visited': False}), (10, {'visited': False}), (11, {'visited': False}), (12, {'visited': False}), (13, {'visited': False}), (14, {'visited': False}), (15, {'visited': False}), (16, {'visited': False}), (17, {'visited': False}), (18, {'visited': False}), (19, {'visited': False})]
    stack-- [17, 2, 15, 8, 3, 7, 0]
    -----
    stack- [17, 2, 15, 8, 3, 7, 0]
    访问 17
    nodes [(0, {'visited': True}), (1, {'visited': False}), (2, {'visited': True}), (3, {'visited': False}), (4, {'visited': False}), (5, {'visited': False}), (6, {'visited': False}), (7, {'visited': True}), (8, {'visited': True}), (9, {'visited': False}), (10, {'visited': False}), (11, {'visited': False}), (12, {'visited': False}), (13, {'visited': False}), (14, {'visited': False}), (15, {'visited': False}), (16, {'visited': False}), (17, {'visited': True}), (18, {'visited': False}), (19, {'visited': False})]
    stack-- [5, 14, 17, 2, 15, 8, 3, 7, 0]
    -----
    stack- [5, 14, 17, 2, 15, 8, 3, 7, 0]
    访问 5
    nodes [(0, {'visited': True}), (1, {'visited': False}), (2, {'visited': True}), (3, {'visited': False}), (4, {'visited': False}), (5, {'visited': True}), (6, {'visited': False}), (7, {'visited': True}), (8, {'visited': True}), (9, {'visited': False}), (10, {'visited': False}), (11, {'visited': False}), (12, {'visited': False}), (13, {'visited': False}), (14, {'visited': False}), (15, {'visited': False}), (16, {'visited': False}), (17, {'visited': True}), (18, {'visited': False}), (19, {'visited': False})]
    stack-- [1, 5, 14, 17, 2, 15, 8, 3, 7, 0]
    -----
    stack- [1, 5, 14, 17, 2, 15, 8, 3, 7, 0]
    访问 1
    nodes [(0, {'visited': True}), (1, {'visited': True}), (2, {'visited': True}), (3, {'visited': False}), (4, {'visited': False}), (5, {'visited': True}), (6, {'visited': False}), (7, {'visited': True}), (8, {'visited': True}), (9, {'visited': False}), (10, {'visited': False}), (11, {'visited': False}), (12, {'visited': False}), (13, {'visited': False}), (14, {'visited': False}), (15, {'visited': False}), (16, {'visited': False}), (17, {'visited': True}), (18, {'visited': False}), (19, {'visited': False})]
    stack-- [19, 10, 4, 1, 5, 14, 17, 2, 15, 8, 3, 7, 0]
    -----
    stack- [19, 10, 4, 1, 5, 14, 17, 2, 15, 8, 3, 7, 0]
    访问 19
    nodes [(0, {'visited': True}), (1, {'visited': True}), (2, {'visited': True}), (3, {'visited': False}), (4, {'visited': False}), (5, {'visited': True}), (6, {'visited': False}), (7, {'visited': True}), (8, {'visited': True}), (9, {'visited': False}), (10, {'visited': False}), (11, {'visited': False}), (12, {'visited': False}), (13, {'visited': False}), (14, {'visited': False}), (15, {'visited': False}), (16, {'visited': False}), (17, {'visited': True}), (18, {'visited': False}), (19, {'visited': True})]
    19 走到尽头
    弹出 19
    stack-- [10, 4, 1, 5, 14, 17, 2, 15, 8, 3, 7, 0]
    -----
    stack- [10, 4, 1, 5, 14, 17, 2, 15, 8, 3, 7, 0]
    访问 10
    nodes [(0, {'visited': True}), (1, {'visited': True}), (2, {'visited': True}), (3, {'visited': False}), (4, {'visited': False}), (5, {'visited': True}), (6, {'visited': False}), (7, {'visited': True}), (8, {'visited': True}), (9, {'visited': False}), (10, {'visited': True}), (11, {'visited': False}), (12, {'visited': False}), (13, {'visited': False}), (14, {'visited': False}), (15, {'visited': False}), (16, {'visited': False}), (17, {'visited': True}), (18, {'visited': False}), (19, {'visited': True})]
    10 走到尽头
    弹出 10
    stack-- [4, 1, 5, 14, 17, 2, 15, 8, 3, 7, 0]
    -----
    stack- [4, 1, 5, 14, 17, 2, 15, 8, 3, 7, 0]
    访问 4
    nodes [(0, {'visited': True}), (1, {'visited': True}), (2, {'visited': True}), (3, {'visited': False}), (4, {'visited': True}), (5, {'visited': True}), (6, {'visited': False}), (7, {'visited': True}), (8, {'visited': True}), (9, {'visited': False}), (10, {'visited': True}), (11, {'visited': False}), (12, {'visited': False}), (13, {'visited': False}), (14, {'visited': False}), (15, {'visited': False}), (16, {'visited': False}), (17, {'visited': True}), (18, {'visited': False}), (19, {'visited': True})]
    4 走到尽头
    弹出 4
    stack-- [1, 5, 14, 17, 2, 15, 8, 3, 7, 0]
    -----
    stack- [1, 5, 14, 17, 2, 15, 8, 3, 7, 0]
    访问 1
    nodes [(0, {'visited': True}), (1, {'visited': True}), (2, {'visited': True}), (3, {'visited': False}), (4, {'visited': True}), (5, {'visited': True}), (6, {'visited': False}), (7, {'visited': True}), (8, {'visited': True}), (9, {'visited': False}), (10, {'visited': True}), (11, {'visited': False}), (12, {'visited': False}), (13, {'visited': False}), (14, {'visited': False}), (15, {'visited': False}), (16, {'visited': False}), (17, {'visited': True}), (18, {'visited': False}), (19, {'visited': True})]
    1 走到尽头
    弹出 1
    stack-- [5, 14, 17, 2, 15, 8, 3, 7, 0]
    -----
    stack- [5, 14, 17, 2, 15, 8, 3, 7, 0]
    访问 5
    nodes [(0, {'visited': True}), (1, {'visited': True}), (2, {'visited': True}), (3, {'visited': False}), (4, {'visited': True}), (5, {'visited': True}), (6, {'visited': False}), (7, {'visited': True}), (8, {'visited': True}), (9, {'visited': False}), (10, {'visited': True}), (11, {'visited': False}), (12, {'visited': False}), (13, {'visited': False}), (14, {'visited': False}), (15, {'visited': False}), (16, {'visited': False}), (17, {'visited': True}), (18, {'visited': False}), (19, {'visited': True})]
    5 走到尽头
    弹出 5
    stack-- [14, 17, 2, 15, 8, 3, 7, 0]
    -----
    stack- [14, 17, 2, 15, 8, 3, 7, 0]
    访问 14
    nodes [(0, {'visited': True}), (1, {'visited': True}), (2, {'visited': True}), (3, {'visited': False}), (4, {'visited': True}), (5, {'visited': True}), (6, {'visited': False}), (7, {'visited': True}), (8, {'visited': True}), (9, {'visited': False}), (10, {'visited': True}), (11, {'visited': False}), (12, {'visited': False}), (13, {'visited': False}), (14, {'visited': True}), (15, {'visited': False}), (16, {'visited': False}), (17, {'visited': True}), (18, {'visited': False}), (19, {'visited': True})]
    stack-- [9, 16, 14, 17, 2, 15, 8, 3, 7, 0]
    -----
    stack- [9, 16, 14, 17, 2, 15, 8, 3, 7, 0]
    访问 9
    nodes [(0, {'visited': True}), (1, {'visited': True}), (2, {'visited': True}), (3, {'visited': False}), (4, {'visited': True}), (5, {'visited': True}), (6, {'visited': False}), (7, {'visited': True}), (8, {'visited': True}), (9, {'visited': True}), (10, {'visited': True}), (11, {'visited': False}), (12, {'visited': False}), (13, {'visited': False}), (14, {'visited': True}), (15, {'visited': False}), (16, {'visited': False}), (17, {'visited': True}), (18, {'visited': False}), (19, {'visited': True})]
    stack-- [18, 9, 16, 14, 17, 2, 15, 8, 3, 7, 0]
    -----
    stack- [18, 9, 16, 14, 17, 2, 15, 8, 3, 7, 0]
    访问 18
    nodes [(0, {'visited': True}), (1, {'visited': True}), (2, {'visited': True}), (3, {'visited': False}), (4, {'visited': True}), (5, {'visited': True}), (6, {'visited': False}), (7, {'visited': True}), (8, {'visited': True}), (9, {'visited': True}), (10, {'visited': True}), (11, {'visited': False}), (12, {'visited': False}), (13, {'visited': False}), (14, {'visited': True}), (15, {'visited': False}), (16, {'visited': False}), (17, {'visited': True}), (18, {'visited': True}), (19, {'visited': True})]
    stack-- [13, 18, 9, 16, 14, 17, 2, 15, 8, 3, 7, 0]
    -----
    stack- [13, 18, 9, 16, 14, 17, 2, 15, 8, 3, 7, 0]
    访问 13
    nodes [(0, {'visited': True}), (1, {'visited': True}), (2, {'visited': True}), (3, {'visited': False}), (4, {'visited': True}), (5, {'visited': True}), (6, {'visited': False}), (7, {'visited': True}), (8, {'visited': True}), (9, {'visited': True}), (10, {'visited': True}), (11, {'visited': False}), (12, {'visited': False}), (13, {'visited': True}), (14, {'visited': True}), (15, {'visited': False}), (16, {'visited': False}), (17, {'visited': True}), (18, {'visited': True}), (19, {'visited': True})]
    13 走到尽头
    弹出 13
    stack-- [18, 9, 16, 14, 17, 2, 15, 8, 3, 7, 0]
    -----
    stack- [18, 9, 16, 14, 17, 2, 15, 8, 3, 7, 0]
    访问 18
    nodes [(0, {'visited': True}), (1, {'visited': True}), (2, {'visited': True}), (3, {'visited': False}), (4, {'visited': True}), (5, {'visited': True}), (6, {'visited': False}), (7, {'visited': True}), (8, {'visited': True}), (9, {'visited': True}), (10, {'visited': True}), (11, {'visited': False}), (12, {'visited': False}), (13, {'visited': True}), (14, {'visited': True}), (15, {'visited': False}), (16, {'visited': False}), (17, {'visited': True}), (18, {'visited': True}), (19, {'visited': True})]
    18 走到尽头
    弹出 18
    stack-- [9, 16, 14, 17, 2, 15, 8, 3, 7, 0]
    -----
    stack- [9, 16, 14, 17, 2, 15, 8, 3, 7, 0]
    访问 9
    nodes [(0, {'visited': True}), (1, {'visited': True}), (2, {'visited': True}), (3, {'visited': False}), (4, {'visited': True}), (5, {'visited': True}), (6, {'visited': False}), (7, {'visited': True}), (8, {'visited': True}), (9, {'visited': True}), (10, {'visited': True}), (11, {'visited': False}), (12, {'visited': False}), (13, {'visited': True}), (14, {'visited': True}), (15, {'visited': False}), (16, {'visited': False}), (17, {'visited': True}), (18, {'visited': True}), (19, {'visited': True})]
    9 走到尽头
    弹出 9
    stack-- [16, 14, 17, 2, 15, 8, 3, 7, 0]
    -----
    stack- [16, 14, 17, 2, 15, 8, 3, 7, 0]
    访问 16
    nodes [(0, {'visited': True}), (1, {'visited': True}), (2, {'visited': True}), (3, {'visited': False}), (4, {'visited': True}), (5, {'visited': True}), (6, {'visited': False}), (7, {'visited': True}), (8, {'visited': True}), (9, {'visited': True}), (10, {'visited': True}), (11, {'visited': False}), (12, {'visited': False}), (13, {'visited': True}), (14, {'visited': True}), (15, {'visited': False}), (16, {'visited': True}), (17, {'visited': True}), (18, {'visited': True}), (19, {'visited': True})]
    stack-- [12, 6, 16, 14, 17, 2, 15, 8, 3, 7, 0]
    -----
    stack- [12, 6, 16, 14, 17, 2, 15, 8, 3, 7, 0]
    访问 12
    nodes [(0, {'visited': True}), (1, {'visited': True}), (2, {'visited': True}), (3, {'visited': False}), (4, {'visited': True}), (5, {'visited': True}), (6, {'visited': False}), (7, {'visited': True}), (8, {'visited': True}), (9, {'visited': True}), (10, {'visited': True}), (11, {'visited': False}), (12, {'visited': True}), (13, {'visited': True}), (14, {'visited': True}), (15, {'visited': False}), (16, {'visited': True}), (17, {'visited': True}), (18, {'visited': True}), (19, {'visited': True})]
    12 走到尽头
    弹出 12
    stack-- [6, 16, 14, 17, 2, 15, 8, 3, 7, 0]
    -----
    stack- [6, 16, 14, 17, 2, 15, 8, 3, 7, 0]
    访问 6
    nodes [(0, {'visited': True}), (1, {'visited': True}), (2, {'visited': True}), (3, {'visited': False}), (4, {'visited': True}), (5, {'visited': True}), (6, {'visited': True}), (7, {'visited': True}), (8, {'visited': True}), (9, {'visited': True}), (10, {'visited': True}), (11, {'visited': False}), (12, {'visited': True}), (13, {'visited': True}), (14, {'visited': True}), (15, {'visited': False}), (16, {'visited': True}), (17, {'visited': True}), (18, {'visited': True}), (19, {'visited': True})]
    6 走到尽头
    弹出 6
    stack-- [16, 14, 17, 2, 15, 8, 3, 7, 0]
    -----
    stack- [16, 14, 17, 2, 15, 8, 3, 7, 0]
    访问 16
    nodes [(0, {'visited': True}), (1, {'visited': True}), (2, {'visited': True}), (3, {'visited': False}), (4, {'visited': True}), (5, {'visited': True}), (6, {'visited': True}), (7, {'visited': True}), (8, {'visited': True}), (9, {'visited': True}), (10, {'visited': True}), (11, {'visited': False}), (12, {'visited': True}), (13, {'visited': True}), (14, {'visited': True}), (15, {'visited': False}), (16, {'visited': True}), (17, {'visited': True}), (18, {'visited': True}), (19, {'visited': True})]
    16 走到尽头
    弹出 16
    stack-- [14, 17, 2, 15, 8, 3, 7, 0]
    -----
    stack- [14, 17, 2, 15, 8, 3, 7, 0]
    访问 14
    nodes [(0, {'visited': True}), (1, {'visited': True}), (2, {'visited': True}), (3, {'visited': False}), (4, {'visited': True}), (5, {'visited': True}), (6, {'visited': True}), (7, {'visited': True}), (8, {'visited': True}), (9, {'visited': True}), (10, {'visited': True}), (11, {'visited': False}), (12, {'visited': True}), (13, {'visited': True}), (14, {'visited': True}), (15, {'visited': False}), (16, {'visited': True}), (17, {'visited': True}), (18, {'visited': True}), (19, {'visited': True})]
    14 走到尽头
    弹出 14
    stack-- [17, 2, 15, 8, 3, 7, 0]
    -----
    stack- [17, 2, 15, 8, 3, 7, 0]
    访问 17
    nodes [(0, {'visited': True}), (1, {'visited': True}), (2, {'visited': True}), (3, {'visited': False}), (4, {'visited': True}), (5, {'visited': True}), (6, {'visited': True}), (7, {'visited': True}), (8, {'visited': True}), (9, {'visited': True}), (10, {'visited': True}), (11, {'visited': False}), (12, {'visited': True}), (13, {'visited': True}), (14, {'visited': True}), (15, {'visited': False}), (16, {'visited': True}), (17, {'visited': True}), (18, {'visited': True}), (19, {'visited': True})]
    17 走到尽头
    弹出 17
    stack-- [2, 15, 8, 3, 7, 0]
    -----
    stack- [2, 15, 8, 3, 7, 0]
    访问 2
    nodes [(0, {'visited': True}), (1, {'visited': True}), (2, {'visited': True}), (3, {'visited': False}), (4, {'visited': True}), (5, {'visited': True}), (6, {'visited': True}), (7, {'visited': True}), (8, {'visited': True}), (9, {'visited': True}), (10, {'visited': True}), (11, {'visited': False}), (12, {'visited': True}), (13, {'visited': True}), (14, {'visited': True}), (15, {'visited': False}), (16, {'visited': True}), (17, {'visited': True}), (18, {'visited': True}), (19, {'visited': True})]
    2 走到尽头
    弹出 2
    stack-- [15, 8, 3, 7, 0]
    -----
    stack- [15, 8, 3, 7, 0]
    访问 15
    nodes [(0, {'visited': True}), (1, {'visited': True}), (2, {'visited': True}), (3, {'visited': False}), (4, {'visited': True}), (5, {'visited': True}), (6, {'visited': True}), (7, {'visited': True}), (8, {'visited': True}), (9, {'visited': True}), (10, {'visited': True}), (11, {'visited': False}), (12, {'visited': True}), (13, {'visited': True}), (14, {'visited': True}), (15, {'visited': True}), (16, {'visited': True}), (17, {'visited': True}), (18, {'visited': True}), (19, {'visited': True})]
    stack-- [11, 15, 8, 3, 7, 0]
    -----
    stack- [11, 15, 8, 3, 7, 0]
    访问 11
    nodes [(0, {'visited': True}), (1, {'visited': True}), (2, {'visited': True}), (3, {'visited': False}), (4, {'visited': True}), (5, {'visited': True}), (6, {'visited': True}), (7, {'visited': True}), (8, {'visited': True}), (9, {'visited': True}), (10, {'visited': True}), (11, {'visited': True}), (12, {'visited': True}), (13, {'visited': True}), (14, {'visited': True}), (15, {'visited': True}), (16, {'visited': True}), (17, {'visited': True}), (18, {'visited': True}), (19, {'visited': True})]
    11 走到尽头
    弹出 11
    stack-- [15, 8, 3, 7, 0]
    -----
    stack- [15, 8, 3, 7, 0]
    访问 15
    nodes [(0, {'visited': True}), (1, {'visited': True}), (2, {'visited': True}), (3, {'visited': False}), (4, {'visited': True}), (5, {'visited': True}), (6, {'visited': True}), (7, {'visited': True}), (8, {'visited': True}), (9, {'visited': True}), (10, {'visited': True}), (11, {'visited': True}), (12, {'visited': True}), (13, {'visited': True}), (14, {'visited': True}), (15, {'visited': True}), (16, {'visited': True}), (17, {'visited': True}), (18, {'visited': True}), (19, {'visited': True})]
    15 走到尽头
    弹出 15
    stack-- [8, 3, 7, 0]
    -----
    stack- [8, 3, 7, 0]
    访问 8
    nodes [(0, {'visited': True}), (1, {'visited': True}), (2, {'visited': True}), (3, {'visited': False}), (4, {'visited': True}), (5, {'visited': True}), (6, {'visited': True}), (7, {'visited': True}), (8, {'visited': True}), (9, {'visited': True}), (10, {'visited': True}), (11, {'visited': True}), (12, {'visited': True}), (13, {'visited': True}), (14, {'visited': True}), (15, {'visited': True}), (16, {'visited': True}), (17, {'visited': True}), (18, {'visited': True}), (19, {'visited': True})]
    8 走到尽头
    弹出 8
    stack-- [3, 7, 0]
    -----
    stack- [3, 7, 0]
    访问 3
    nodes [(0, {'visited': True}), (1, {'visited': True}), (2, {'visited': True}), (3, {'visited': True}), (4, {'visited': True}), (5, {'visited': True}), (6, {'visited': True}), (7, {'visited': True}), (8, {'visited': True}), (9, {'visited': True}), (10, {'visited': True}), (11, {'visited': True}), (12, {'visited': True}), (13, {'visited': True}), (14, {'visited': True}), (15, {'visited': True}), (16, {'visited': True}), (17, {'visited': True}), (18, {'visited': True}), (19, {'visited': True})]
    3 走到尽头
    弹出 3
    stack-- [7, 0]
    -----
    stack- [7, 0]
    访问 7
    nodes [(0, {'visited': True}), (1, {'visited': True}), (2, {'visited': True}), (3, {'visited': True}), (4, {'visited': True}), (5, {'visited': True}), (6, {'visited': True}), (7, {'visited': True}), (8, {'visited': True}), (9, {'visited': True}), (10, {'visited': True}), (11, {'visited': True}), (12, {'visited': True}), (13, {'visited': True}), (14, {'visited': True}), (15, {'visited': True}), (16, {'visited': True}), (17, {'visited': True}), (18, {'visited': True}), (19, {'visited': True})]
    7 走到尽头
    弹出 7
    stack-- [0]
    -----
    stack- [0]
    访问 0
    nodes [(0, {'visited': True}), (1, {'visited': True}), (2, {'visited': True}), (3, {'visited': True}), (4, {'visited': True}), (5, {'visited': True}), (6, {'visited': True}), (7, {'visited': True}), (8, {'visited': True}), (9, {'visited': True}), (10, {'visited': True}), (11, {'visited': True}), (12, {'visited': True}), (13, {'visited': True}), (14, {'visited': True}), (15, {'visited': True}), (16, {'visited': True}), (17, {'visited': True}), (18, {'visited': True}), (19, {'visited': True})]
    0 走到尽头
    弹出 0
    stack-- []
    search_path [0, 7, 3, 8, 15, 11, 2, 17, 14, 16, 6, 12, 9, 18, 13, 5, 1, 4, 10, 19]
    
    ==对比深度搜索遍历结果==
    networkx dfs [0, 7, 3, 8, 15, 11, 2, 17, 14, 16, 6, 12, 9, 18, 13, 5, 1, 4, 10, 19]

[watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBAemhhbmdwaGls_size_20_color_FFFFFF_t_70_g_se_x_16]: https://img-blog.csdnimg.cn/a1c634bdb1014d31832572a1ac94c76c.png?x-oss-process=image/watermark,type_ZHJvaWRzYW5zZmFsbGJhY2s,shadow_50,text_Q1NETiBAemhhbmdwaGls,size_20,color_FFFFFF,t_70,g_se,x_16