邻接矩阵有向图

和无向图的非常相似，只是反向不记录为1而已

#include 
#include 
#include 
#include 

#define MAX 100
#define isLetter(a)  ((((a)>='a')&&((a)<='z')) || (((a)>='A')&&((a)<='Z')))
#define LENGTH(a)  (sizeof(a)/sizeof(a[0]))

// 邻接矩阵
typedef struct _graph
{
	char vexs[MAX];       // 顶点集合
	int vexnum;           // 顶点数
	int edgnum;           // 边数
	int matrix[MAX][MAX]; // 邻接矩阵
}Graph, *PGraph;

/*
* 返回ch在matrix矩阵中的位置
*/
static int get_position(Graph g, char ch)
{
	int i;
	for (i = 0; i(v * (v - 1))))
	{
		printf("input error: invalid parameters!\n");
		return NULL;
	}

	if ((pG = (Graph*)malloc(sizeof(Graph))) == NULL)
		return NULL;
	memset(pG, 0, sizeof(Graph));

	// 初始化"顶点数"和"边数"
	pG->vexnum = v;
	pG->edgnum = e;
	// 初始化"顶点"
	for (i = 0; i < pG->vexnum; i++)
	{
		printf("vertex(%d): ", i);
		pG->vexs[i] = read_char();
	}

	// 初始化"边"
	for (i = 0; i < pG->edgnum; i++)
	{
		// 读取边的起始顶点和结束顶点
		printf("edge(%d):", i);
		c1 = read_char();
		c2 = read_char();

		p1 = get_position(*pG, c1);
		p2 = get_position(*pG, c2);
		if (p1 == -1 || p2 == -1)
		{
			printf("input error: invalid edge!\n");
			free(pG);
			return NULL;
		}

		pG->matrix[p1][p2] = 1;
	}

	return pG;
}

/*
* 创建图(用已提供的矩阵)
*/
Graph* create_example_graph()
{
	char vexs[] = { 'A', 'B', 'C', 'D', 'E', 'F', 'G' };
	char edges[][2] = {
		{ 'A', 'B' },
		{ 'B', 'C' },
		{ 'B', 'E' },
		{ 'B', 'F' },
		{ 'C', 'E' },
		{ 'D', 'C' },
		{ 'E', 'B' },
		{ 'E', 'D' },
		{ 'F', 'G' } };
	int vlen = LENGTH(vexs);
	int elen = LENGTH(edges);
	int i, p1, p2;
	Graph* pG;

	// 输入"顶点数"和"边数"
	if ((pG = (Graph*)malloc(sizeof(Graph))) == NULL)
		return NULL;
	memset(pG, 0, sizeof(Graph));

	// 初始化"顶点数"和"边数"
	pG->vexnum = vlen;
	pG->edgnum = elen;
	// 初始化"顶点"
	for (i = 0; i < pG->vexnum; i++)
	{
		pG->vexs[i] = vexs[i];
	}

	// 初始化"边"
	for (i = 0; i < pG->edgnum; i++)
	{
		// 读取边的起始顶点和结束顶点
		p1 = get_position(*pG, edges[i][0]);
		p2 = get_position(*pG, edges[i][1]);

		pG->matrix[p1][p2] = 1;
	}

	return pG;
}

/*
* 打印矩阵队列图
*/
void print_graph(Graph G)
{
	int i, j;

	printf("Martix Graph:\n");
	for (i = 0; i < G.vexnum; i++)
	{
		for (j = 0; j < G.vexnum; j++)
			printf("%d ", G.matrix[i][j]);
		printf("\n");
	}
}

void main()
{
	Graph* pG;

	// 自定义"图"(输入矩阵队列)
	//pG = create_graph();
	// 采用已有的"图"
	pG = create_example_graph();

	print_graph(*pG);       // 打印图
}