使用c语言写一个代码假设无向连通图采用邻接表存储。设计一个算法输出图G的一颗深度优先生成树

好的，这是一个关于无向连通图的算法问题，我可以回答。以下是用C语言编写的代码，实现输出图G的一颗深度优先生成树：

#include <stdio.h>
#include <stdlib.h>

#define MAX_VERTICES 100

typedef struct _node {
    int vertex;
    struct _node *next;
} node;

node *graph[MAX_VERTICES] = { NULL };
int visited[MAX_VERTICES] = { 0 };

void add_edge(int u, int v) {
    node *new_node = (node*)malloc(sizeof(node));
    new_node->vertex = v;
    new_node->next = graph[u];
    graph[u] = new_node;
}

void dfs(int v) {
    visited[v] = 1;
    printf("%d ", v);

    node *adj_list = graph[v];
    while (adj_list != NULL) {
        int connected_vertex = adj_list->vertex;
        if (!visited[connected_vertex]) {
            dfs(connected_vertex);
        }
        adj_list = adj_list->next;
    }
}

void dfs_spanning_tree(int v) {
    visited[v] = 1;

    node *adj_list = graph[v];
    while (adj_list != NULL) {
        int connected_vertex = adj_list->vertex;
        if (!visited[connected_vertex]) {
            printf("(%d,%d) ", v, connected_vertex);
            dfs_spanning_tree(connected_vertex);
        }
        adj_list = adj_list->next;
    }
}

int main() {
    int vertices, edges, i, u, v;

    printf("Enter the number of vertices: ");
    scanf("%d", &vertices);

    printf("Enter the number of edges: ");
    scanf("%d", &edges);

    for (i = 0; i < edges; i++) {
        printf("Enter the edge (u, v): ");
        scanf("%d%d", &u, &v);
        add_edge(u, v);
        add_edge(v, u);
    }

    printf("\nDepth First Traversal: ");
    dfs(0);

    printf("\n\nDepth First Spanning Tree: ");
    dfs_spanning_tree(0);

    return 0;
}

这段代码使用邻接表存储无向连通图，通过深度优先搜索算法实现输出一颗深度优先生成树。