hdu1233 还是畅通工程

#include <cstdio>
#include <algorithm>
using namespace std;

int father[102];
struct node
{
	int a,b,value;
}w[5002];

bool cmp(const node &a,const node &b)
{
	return a.value<b.value;
}

int find(int x)
{
	if(x!=father[x])
		father[x]=find(father[x]);
	return father[x];
}
void merge(int x,int y,int z,int *tp)
{
	int a,b;
	a=find(x);
	b=find(y);
	if(a!=b)
	{
		(*tp)+=z;
		father[a]=b;
	}
}
int main()
{
	int n,m,sum;
	while(scanf("%d",&n)&&n)
	{
		sum=0;
		m=n*(n-1)/2;
		for(int i=1;i<=m;i++)
			scanf("%d %d %d",&w[i].a,&w[i].b,&w[i].value);
		sort(w+1,w+m+1,cmp);//按边长从小到大排序
		for(int i=1;i<=n;i++)
			father[i]=i;
		for (int i=1;i<=m;i++)
		{
			merge(w[i].a,w[i].b,w[i].value,&sum);
		}
		printf("%d\n",sum);
	}
}

//克鲁卡斯算法，最小生成树