题目链接
http://acm.hdu.edu.cn/showproblem.php?pid=1233
题目很简单(最小生成树)
#include<cstdio>
#include<iostream>
#include<algorithm>
using namespace std;
struct node
{
    int x,y,d;
}s[5000];
int father[111];
int sum;
bool cmp(const node &a,const node &b)
{
    return a.d<b.d;
}
int Find(int x)
{
    if(x==father[x]) return x;
    father[x]=Find(father[x]);
    return father[x];
}
void Union(int x,int y,int d)
{
    x=Find(x);
    y=Find(y);
    if(x!=y)
    {
        father[x]=y;
        sum=sum+d;
    }
}
int main(void)
{
    int n,m,i,j,k,l;
    while(scanf("%d",&n)==1&&n)
    {
        m=n*(n-1)/2;
        for(i=0;i<m;i++)
        scanf("%d%d%d",&s[i].x,&s[i].y,&s[i].d);
        sort(s,s+m,cmp);
        for(i=1;i<=n;i++)
        father[i]=i;
        sum=0;
        for(i=0;i<m;i++)
        {
            Union(s[i].x,s[i].y,s[i].d);
        }
        printf("%d\n",sum);
    }
    return 0;
}