#include <stdio.h>#include <string.h>#define MAX 110#define INF 100000000int graph[MAX][MAX] ;bool visited[MAX] ;int prim(int n){int closest[MAX] ;int lowcost[MAX] ;memset(visited,false,sizeof(visited)) ;for(int i = 1 ; i <= n ; ++i){closest[i] = 1;lowcost[i] = graph[1][i] ;}visited[1] = true ;for(int i = 1 ; i <= n ; ++i){int temp = INF ;int t = 1 ;for(int j = 1 ; j <= n ; ++j){if(!visited[j] && temp>lowcost[j]){temp = lowcost[j] ;t = j ;}}if(temp == INF){break ;}visited[t] = true ;for(int j = 1 ; j <= n ; ++j){if(!visited[j] && lowcost[j]>graph[t][j]){lowcost[j] = graph[t][j] ;closest[j] = t ;}}}int sum = 0 ;for(int i = 2 ; i <= n ; ++i){sum += lowcost[i] ;}return sum ;}int main(){int n = 0 ;while(scanf("%d",&n) && n){int m = (n*(n-1))/2 ;for(int i = 0 ; i <= n ; ++i){for(int j = 0 ; j <= i ; ++j){graph[i][j] = graph[j][i] = INF ;}}for(int i = 1 ; i <= m ; ++i){int x,y,w,flag;scanf("%d%d%d%d",&x,&y,&w,&flag);if(flag){graph[x][y] = graph[y][x] = 0;}else{graph[x][y] = graph[y][x] = w ;}}int ans = prim(n);printf("%d\n",ans) ;}return 0 ;}与君共勉
，昨晚多几分钟的准备，今天少几小时的麻烦。
