问题描述】编程实现有向图图的邻接矩阵存储，并计算给定结点的入度和初度。 如有向图： 51097d4665434b54a8ff4c6ff2ff9a43.jpg 【输入形式】 【输出形式】 【样例输入】(所有数据从键盘输入） 4 4 A B C D A B A D B C C A A 【样例输出】 This graph has 4 vertexs, and 4 edges. The information of vertexs are: A 0 B 1 C 2 D 3 The adjacent matrix of graph is: 0 1 0 1 0 0 1 0 1 0 0 0 0 0 0 0 The in-degree of A is 1 The out-degree of A is 2 【样例说明】 【评分标准】 #include<iostream> #include<string> #include<cstring> #include<fstream> using namespace std; const int MAXL = 20; struct Node {//结点 string data;//结点值 int no;//结点编号 Node(string data):data(data),no(0){} Node() { data = ""; no = 0; } }; struct MGraph { int n, e;//顶点数和边数 Node VEXS[MAXL];//顶点数组 int Edge[MAXL][MAXL];//邻接矩阵 MGraph() { n = e = 0; memset(Edge, 0, sizeof(Edge)); } };

以下是 C++ 代码实现：

#include <iostream>
#include <string>
#include <cstring>
using namespace std;

const int MAXL = 20;

struct Node {
    string data;  // 结点值
    int no;  // 结点编号
    Node(string data):data(data),no(0) {}
    Node() { data = ""; no = 0; }
};

struct MGraph {
    int n, e;  // 顶点数和边数
    Node VEXS[MAXL];  // 顶点数组
    int Edge[MAXL][MAXL];  // 邻接矩阵

    MGraph() {
        n = e = 0;
        memset(Edge, 0, sizeof(Edge));
    }
};

int main() {
    MGraph g;

    // 输入有向图信息
    cin >> g.n >> g.e;
    for (int i = 0; i < g.n; i++) {
        cin >> g.VEXS[i].data;
        g.VEXS[i].no = i;
    }
    for (int i = 0; i < g.e; i++) {
        string u, v;
        cin >> u >> v;
        int x = -1, y = -1;
        for (int j = 0; j < g.n; j++) {
            if (g.VEXS[j].data == u) x = j;
            if (g.VEXS[j].data == v) y = j;
        }
        g.Edge[x][y] = 1;
    }

    // 输出有向图信息
    cout << "This graph has " << g.n << " vertexs, and " << g.e << " edges." << endl;
    cout << "The information of vertexs are:" << endl;
    for (int i = 0; i < g.n; i++) {
        cout << g.VEXS[i].data << " " << g.VEXS[i].no << " ";
    }
    cout << endl;
    cout << "The adjacent matrix of graph is:" << endl;
    for (int i = 0; i < g.n; i++) {
        for (int j = 0; j < g.n; j++) {
            cout << g.Edge[i][j] << " ";
        }
        cout << endl;
    }

    // 计算给定结点的入度和出度
    string target;
    cin >> target;
    int in_degree = 0, out_degree = 0;
    for (int i = 0; i < g.n; i++) {
        if (g.VEXS[i].data == target) {
            for (int j = 0; j < g.n; j++) {
                if (g.Edge[j][i]) in_degree++;
                if (g.Edge[i][j]) out_degree++;
            }
            break;
        }
    }
    cout << "The in-degree of " << target << " is " << in_degree << endl;
    cout << "The out-degree of " << target << " is " << out_degree << endl;

    return 0;
}

其中，`Node` 结构体表示有向图的结点，`MGraph` 结构体表示有向图。`main` 函数中，首先输入有向图信息，包括顶点数、边数、结点值和边的信息，并构建邻接矩阵。然后输出有向图信息，包括顶点数、边数和每个结点的信息，以及邻接矩阵。最后输入给定结点的值，并计算该结点的入度和出度，并输出结果。

例如，对于输入样例：

4 4
A B C D
A B
A D
B C
C A
A

程序输出：

This graph has 4 vertexs, and 4 edges.
The information of vertexs are:
A 0 B 1 C 2 D 3 
The adjacent matrix of graph is:
0 1 0 1 
0 0 1 0 
1 0 0 0 
0 0 0 0 
The in-degree of A is 1
The out-degree of A is 2

其中，第 1 行表示有向图有 4 个结点和 4 条边；第 2 行表示每个结点的值和编号；第 3~6 行表示邻接矩阵；第 7、8 行表示给定结点 A 的入度和出度。