dfs算法有向图c语言

以下是使用深度优先搜索（DFS）算法遍历有向图的 C 语言代码示例：

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

#define MAX_VERTICES 100

typedef struct Node {
    int vertex;
    struct Node* next;
} Node;

Node* createNode(int v) {
    Node* newNode = (Node*) malloc(sizeof(Node));
    newNode->vertex = v;
    newNode->next = NULL;
    return newNode;
}

void addEdge(Node* adj[], int src, int dest) {
    Node* newNode = createNode(dest);
    newNode->next = adj[src];
    adj[src] = newNode;
}

int visited[MAX_VERTICES] = {0};

void DFS(Node* adj[], int start) {
    visited[start] = 1;
    printf("%d ", start);

    Node* temp = adj[start];
    while (temp != NULL) {
        int connectedVertex = temp->vertex;
        if (!visited[connectedVertex]) {
            DFS(adj, connectedVertex);
        }
        temp = temp->next;
    }
}

int main() {
    Node* adj[MAX_VERTICES];

    int numVertices, numEdges;
    printf("Enter the number of vertices and edges: ");
    scanf("%d%d", &numVertices, &numEdges);

    for (int i = 0; i < numVertices; i++) {
        adj[i] = NULL;
    }

    int src, dest;
    printf("Enter the edges (source, destination):\n");
    for (int i = 0; i < numEdges; i++) {
        scanf("%d%d", &src, &dest);
        addEdge(adj, src, dest);
    }

    int startVertex;
    printf("Enter the starting vertex for DFS: ");
    scanf("%d", &startVertex);

    printf("DFS traversal starting from vertex %d: ", startVertex);
    DFS(adj, startVertex);

    return 0;
}

这段代码使用邻接链表来存储有向图，然后使用 DFS 算法遍历图中所有节点。其中，`addEdge` 函数用于向邻接链表中添加边，`DFS` 函数用于递归遍历所有与当前节点相连的未访问过的节点。最后，用户需要输入起始节点，程序将从该节点开始遍历整个图，并输出遍历的结果。