C语言拓扑排序代码怎么写

下面是一个用C语言实现拓扑排序的示例代码：

#include <stdio.h>#include <stdbool.h>#define MAXVERTICES 100struct Graph {    int vertices;    int edges;    int adjacencyMatrix[MAXVERTICES][MAXVERTICES];};void initializeGraph(struct Graph* graph, int vertices) {    graph->vertices = vertices;    graph->edges = 0;    for (int i = 0; i < vertices; i++) {        for (int j = 0; j < vertices; j++) {            graph->adjacencyMatrix[i][j] = 0;        }    }}void addEdge(struct Graph* graph, int startVertex, int endVertex) {    graph->adjacencyMatrix[startVertex][endVertex] = 1;    graph->edges++;}void topologicalSortUtil(struct Graph* graph, int vertex, bool visited[], int stack[], int* stackIndex) {    visited[vertex] = true;    for (int i = 0; i < graph->vertices; i++) {        if (graph->adjacencyMatrix[vertex][i] == 1 && !visited[i]) {            topologicalSortUtil(graph, i, visited, stack, stackIndex);        }    }    stack[(*stackIndex)++] = vertex;}void topologicalSort(struct Graph* graph) {    bool visited[MAXVERTICES] = {false};    int stack[MAXVERTICES];    int stackIndex = 0;    for (int i = 0; i < graph->vertices; i++) {        if (!visited[i]) {            topologicalSortUtil(graph, i, visited, stack, &stackIndex);        }    }    printf("Topological Sort: ");    while (stackIndex > 0) {        printf("%d ", stack[--stackIndex]);    }    printf("\n");}int main() {    struct Graph graph;    int vertices, edges, startVertex, endVertex;    printf("Enter the number of vertices in the graph: ");    scanf("%d", &vertices);    initializeGraph(&graph, vertices);    printf("Enter the number of edges in the graph: ");    scanf("%d", &edges);    for (int i = 0; i < edges; i++) {        printf("Enter the start and end vertex of edge %d: ", i + 1);        scanf("%d %d", &startVertex, &endVertex);        addEdge(&graph, startVertex, endVertex);    }    topologicalSort(&graph);    return 0;}

这个代码中，首先定义了一个结构体Graph来表示图，其中vertices表示顶点的个数，edges表示边的个数，adjacencyMatrix表示邻接矩阵。

然后定义了几个函数来操作图，包括initializeGraph用于初始化图，addEdge用于添加边，topologicalSortUtil用于递归实现拓扑排序，topologicalSort用于调用topologicalSortUtil进行拓扑排序。

在main函数中，首先获取用户输入的顶点个数和边的个数，然后通过addEdge函数添加边，最后调用topologicalSort函数进行拓扑排序。

注意：该示例代码中使用邻接矩阵来表示图，适用于边数较少的情况。如果边数较多，推荐使用邻接表来表示图。