拓扑排序

#include <stdio.h>  
#include <stdlib.h>  
#include <string.h>  
  
#define MaxSize 20  
  
typedef char VertexType;  
  
typedef struct outNode {        //定义出度的节点，边表 
    VertexType data;  
    struct outNode *next;  
}outNode;  
  
typedef struct Vertex {         //定义顶点结构  
    int in;  
    VertexType data;  
    outNode *first;  
}Vertex;  
  
//用邻接表法创建AOV网  
void CreateAOV( Vertex **g )  
{  
    VertexType ver;  
    int i = 0;  
    int VertexNum;  
    outNode *p, *q;   
    (*g) = (Vertex *)malloc(sizeof(Vertex)*MaxSize);  
  
    printf("请输入AOV网的顶点:\n");                  
    while( '\n' != (ver=getchar()) ) {      //存储网的顶点信息  
        (*g)[i].data = ver;  
        (*g)[i].first = NULL;  
        i++;  
    }  
    (*g)[i].data = '\0';  			//最后一个顶点储存'\0' 
    VertexNum = i;                          //记录顶点数  
  
    printf("请依次输入AOV网顶点的入度:\n");  
    for( i=0; i<VertexNum; i++ )         //存储顶点的入度信息  
        scanf("%d", &(*g)[i].in);  
  
    fflush(stdin);  //清空缓冲区 
      
    printf("请输入AOV网顶点对应邻接点:\n");  
    for( i=0; i<VertexNum; i++ ) {           //存储每个顶点的邻接点信息  
        printf("%c :", (*g)[i].data);  
        if( '\n' != (ver=getchar()) ) {  
            p = (outNode *)malloc(sizeof(outNode));  
            p->data = ver;  
            (*g)[i].first = p;  
            p->next = NULL;  
            q = p;  
            while( '\n' != (ver=getchar()) ) {  
                p = (outNode *)malloc(sizeof(outNode));  
                p->data = ver;  
                p->next = NULL;  
                q->next = p;  
                q = p;  
            }  
        }  
    }  
}  
  
//获取顶点数  
int CalVerNum( Vertex *g )  
{  
    int len = 0;  
    while( '\0' != (g++)->data )   
        len++;  
    return len;  
}  
  
  
//打印AOV网  
void PrintAOV( Vertex *g )  
{  
    int VertexNum = CalVerNum( g );  
    outNode *p;  
    printf("AOV的顶点、入度以及邻接点为:\n");  
    for( int i=0; i<VertexNum; i++ ) {       //打印顶点  
        printf("%c  %d  ", g[i].data, g[i].in);  
        p = g[i].first;  
        while( NULL != p ) {  
            printf("%c ", p->data);  
            p = p->next;  
        }  
        printf("\n");  
    }  
}  
  
//拓扑排序函数  
void TopSort( Vertex *g )  
{  
    int i, j, k;  
    outNode *p;  
    int VertexNum = CalVerNum( g );  
    printf("拓扑排序后的序列为:\n");  
    for( i=0; i<VertexNum; i++ ) 
	{               //外循环用来控制输出的顶点数  
        for( j=0; j<VertexNum; j++ )         //内循环用来找到下一个入度为0的顶点  
            if( 0 == g[j].in ) 
			{  
                printf("%c ", g[j].data);  
                g[j].in = -1;  
                p = g[j].first;  
                while( NULL != p ) 
				{            //删除所有从该顶点发出的全部有向边,具体就是逐个找到该顶点邻接点，然后将其入度-1  
                    for( k=0; k<VertexNum; k++ )  
                        if( p->data == g[k].data )
						{  
                            g[k].in--;  
                            break;  
                        }  
                    p = p->next;  
                }  
                break;  
            }  
    }  
    printf("\n");  
}  
  
int main()  
{  
    Vertex *g;  
    CreateAOV( &g );  
  
    PrintAOV( g );  
  
    TopSort( g );  
  
    return 0;  
} 

来源：CSDN

作者：qq_41017546

链接：https://blog.csdn.net/qq_41017546/article/details/104657341