【王道】最小生成树、并查集

【题意】输入n村庄，接下来输入n*（n-1）/2条路以及路的权值。输出最小生成树的长度

#include<iostream>
#include<cstring>
#include<vector>
#include<math.h>
#include<algorithm>
using namespace std;
int tree[101];
int friends[101];
int finderoot(int x)
{
	if(tree[x]==-1)return x;
	else
	{
		int temp=finderoot(tree[x]);
		tree[x]=temp;
		return temp;
	}
}
struct edge
{
	int a,b,c;
}edges[100];
bool cmp(edge m,edge n)
{
	return m.c<n.c;
}
int main(int argc, char const *argv[])
{
	int n,a,b,c,count,cost;
	while(cin>>n)
	{
		if(n==0)break;
		count=0;
		cost=0;
		fill(tree,tree+100,-1);
		memset(edges,0,sizeof(edges));
		int bound=n*(n-1)/2;
		for(int i=1;i<=bound;i++)
		{
			cin>>a>>b>>c;
			edges[count].a=a;
			edges[count].b=b;
			edges[count].c=c;
			count++;
		}
		sort(edges,edges+count,cmp);
		for(int i=0;i<count;i++)
		{
			a=edges[i].a;
			b=edges[i].b;
			a=finderoot(a);
			b=finderoot(b);
			if(a!=b) 
			{
				tree[a]=b;
				cost+=edges[i].c;
			}
		}
		cout<<cost<<endl;

	}
	return 0;
}