用C语言写一段代码，有向无权图的建立、删除、修改、查询并用拓扑排序检验连通性，用邻接矩阵存储，可以从文件读取数据 并进行键盘操作

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

#define MAX_VERTEX_NUM 100 // 定义图中最大顶点数
#define MAX_EDGE_NUM 10000 // 定义图中最大边数

// 定义邻接矩阵存储结构体
typedef struct {
    int edges[MAX_VERTEX_NUM][MAX_VERTEX_NUM]; // 存储各条边的信息
    int vertex_num; // 存储顶点数
    int edge_num; // 存储边数
} Graph;

// 创建图
void createGraph(Graph* graph) {
    printf("请输入顶点数和边数：\n");
    scanf("%d%d", &graph->vertex_num, &graph->edge_num);

    // 初始化邻接矩阵
    for (int i = 0; i < graph->vertex_num; i++) {
        for (int j = 0; j < graph->vertex_num; j++) {
            graph->edges[i][j] = 0;
        }
    }

    // 添加边
    printf("请输入每条边的起点和终点：\n");
    for (int i = 0; i < graph->edge_num; i++) {
        int start, end;
        scanf("%d%d", &start, &end);
        graph->edges[start][end] = 1;
    }
}

// 删除边
void deleteEdge(Graph* graph) {
    int start, end;
    printf("请输入要删除的边的起点和终点：\n");
    scanf("%d%d", &start, &end);
    if (graph->edges[start][end] == 1) {
        graph->edges[start][end] = 0;
        printf("删除成功！\n");
    } else {
        printf("该边不存在！\n");
    }
}

// 修改边
void modifyEdge(Graph* graph) {
    int start, end;
    printf("请输入要修改的边的起点和终点：\n");
    scanf("%d%d", &start, &end);
    if (graph->edges[start][end] == 1) {
        graph->edges[start][end] = 0;
        printf("请输入修改后的终点：\n");
        scanf("%d", &end);
        graph->edges[start][end] = 1;
        printf("修改成功！\n");
    } else {
        printf("该边不存在！\n");
    }
}

// 查询边
void queryEdge(Graph* graph) {
    int start, end;
    printf("请输入要查询的边的起点和终点：\n");
    scanf("%d%d", &start, &end);
    if (graph->edges[start][end] == 1) {
        printf("该边存在！\n");
    } else {
        printf("该边不存在！\n");
    }
}

// 拓扑排序
int topologicalSort(Graph* graph) {
    int inDegree[MAX_VERTEX_NUM] = {0}; // 存储每个顶点的入度
    int queue[MAX_VERTEX_NUM], front = 0, rear = -1; // 定义队列
    int count = 0; // 存储已经输出的顶点数

    // 计算每个顶点的入度
    for (int i = 0; i < graph->vertex_num; i++) {
        for (int j = 0; j < graph->vertex_num; j++) {
            if (graph->edges[i][j] == 1) {
                inDegree[j]++;
            }
        }
    }

    // 将入度为0的顶点入队
    for (int i = 0; i < graph->vertex_num; i++) {
        if (inDegree[i] == 0) {
            queue[++rear] = i;
        }
    }

    // 拓扑排序
    while (front <= rear) {
        int current_vertex = queue[front++]; // 出队一个顶点
        printf("%d ", current_vertex); // 输出该顶点

        // 将该顶点能够到达的顶点的入度减1
        for (int i = 0; i < graph->vertex_num; i++) {
            if (graph->edges[current_vertex][i] == 1) {
                inDegree[i]--;
                if (inDegree[i] == 0) { // 如果该顶点的入度为0，将其入队
                    queue[++rear] = i;
                }
            }
        }

        count++;
    }

    if (count == graph->vertex_num) { // 如果已经输出了所有顶点，说明图是连通的
        printf("\n图是连通的！\n");
        return 1;
    } else {
        printf("\n图不是连通的！\n");
        return -1;
    }
}

// 键盘操作
void keyboardOperation(Graph* graph) {
    int choice;
    while (1) {
        printf("\n请选择您要执行的操作：\n");
        printf("1. 创建图\n");
        printf("2. 删除边\n");
        printf("3. 修改边\n");
        printf("4. 查询边\n");
        printf("5. 拓扑排序并检验连通性\n");
        printf("6. 退出程序\n");
        scanf("%d", &choice);
        switch (choice) {
            case 1:
                createGraph(graph);
                break;
            case 2:
                deleteEdge(graph);
                break;
            case 3:
                modifyEdge(graph);
                break;
            case 4:
                queryEdge(graph);
                break;
            case 5:
                topologicalSort(graph);
                break;
            case 6:
                exit(0);
            default:
                printf("输入有误，请重新输入！\n");
        }
    }
}

int main() {
    Graph graph;
    keyboardOperation(&graph);
    return 0;
}