3
1 2 1 0
1 3 2 0
2 3 4 0
3
1 2 1 0
1 3 2 0
2 3 4 1
3
1 2 1 0
1 3 2 1
2 3 4 1
0

3
1
0

#include<stdio.h>
#include<algorithm>
using namespace std;
//kruskal
int N,ut;
int root[101];
typedef struct _node{
	int x,y,dis,sty;
}Node;
Node graph[5050];
int cmp(Node n,Node m){
	return n.dis<m.dis;
}
int find(int i){  
	return root[i]=(root[i]==i?i:find(root[i]));
}
void unio (int i,int j){
    if(i>=j)
     root[i]=j;
    else root[j]=i;
}
int kruskal(){
	sort(graph,graph+ut,cmp);
	int shortest =0;
	for(int i=0;i<ut;++i){   //老范低级错误,这里误写成了 i < N* N, runtime ...了 N次~~~~~~~~
		int t,k;
		t=find(graph[i].x);
		k=find(graph[i].y);
		if(t!=k){
			shortest= shortest+graph[i].dis;
			unio(t,k);
		}
	}
	return shortest;
}
int main(){
	while(~scanf("%d",&N),N){
		ut=N%2==0?N/2*(N-1):(N-1)/2*N;
		int i,a,b,c,d;
		for(i=1;i<=N;++i){
			root[i]=i;
		}
		for(i=0;i<ut;++i){
			scanf("%d%d%d%d",&a,&b,&c,&d);	  
			graph[i].x=a;graph[i].y=b;graph[i].dis=c;graph[i].sty=d;
		    if(d)
			  graph[i].dis=0;//unio(a,b);
		} 
		printf("%d\n",kruskal());
	}
	return 0;
}