离散数学实验报告(三)

一、实验内容：Kruskal算法求解最小生成树
二、实验源码：
#include<stdio.h>
#include<stdlib.h>
#include<malloc.h>
#define MAX 100
struct Node{
int vertex1;
int vertex2;
int weight;
struct Node *next;
};
typedef struct Node * Edge;
Edge head = NULL;
int visited[MAX];
Edge read(){
int v1, v2, w;
Edge newNode = NULL, pointer = NULL;
while(1){
scanf("%d %d %d", &v1, &v2, &w);
if(v1 == -1 || v2 == -1 || w == -1)
break;
newNode = (Edge)malloc(sizeof(struct Node));
newNode->vertex1 = v1;
newNode->vertex2 = v2;
newNode->weight = w;
newNode->next = NULL;
pointer = head;
if(pointer == NULL)
head = newNode;
else{
if(newNode->weight < pointer->weight){
newNode->next = pointer;
head = newNode;
}else{
while(pointer != NULL && pointer->next != NULL){
if(pointer->weight < newNode->weight && newNode->weight < pointer->next->weight){
newNode->next = pointer->next;
pointer->next = newNode;
break;
}
pointer = pointer->next;
}
pointer->next = newNode;
}
}
}
return head;
}
void printLink(Edge edge){
Edge pointer = edge;
printf("\n\n图中所有边按权值递增的排序如下: \n");
while(pointer != NULL){
printf("[%d %d]", pointer->vertex1, pointer->vertex2);
printf("(%d)",pointer->weight);
if(pointer->next != NULL)
printf(" ==> ");
pointer = pointer->next;
}
printf("\n");
}
void kruskal(Edge edge, int vexnum){
int visitedEdgeNum = 0, weight = 0;
printf("\n最小生成树的路径为: \n");
while(visitedEdgeNum < vexnum){
if(visited[edge->vertex1] == 0 || visited[edge->vertex2] == 0){ printf("[%d %d]", edge->vertex1, edge->vertex2);
printf("(%d) ",edge->weight);
weight += edge->weight; visitedEdgeNum++;
visited[edge->vertex1] = 1;
visited[edge->vertex2] = 1;
}
edge = edge->next;
if(edge == NULL){
break;
}
}
printf("\n\n最短路径长度为：%d \n\n", weight);
}
void main(){
int vexnum, i;
Edge edge = NULL;
printf("请输入定点个数、各顶点和权值：\n输入形式如下：n i j w ... -1 -1 -1\nn 表示图的顶点个数，i j w 表示从顶点i 到顶点j 的权为w 的一条边，均以-1结尾。

\n");
scanf("%d", &vexnum);
for(i=0; i<vexnum; i++)
visited[i] = 0;
edge = read();
printLink(edge);
kruskal(edge, vexnum);
}。