#include<iostream>
#include<string>
#include<string.h>
#include<vector>
#include<stdio.h>
#include<algorithm>
using namespace std;

struct node
{
	int u;
	int v;
	int weight;
	int state;
}griph[105];
int a[105];
bool compare(node a,node b)
{
	if(a.state ==b.state )//同状态返回权值小
		return a.weight <b.weight ;
	else//不同优先已建
		return a.state>b.state;
}

int find(int x)
{
	if(x==a[x])return x;
	a[x]=find(a[x]);
	return a[x];
}
int main()
{
	int n;
	while(cin>>n)
	{
		if(n==0)break;
		int hang=n*(n-1)/2;
		int sum=0,flag=0;
		for(int i=1;i<=n;i++)
			a[i]=i;
		//输入
		for(int i=0;i<hang;i++)
		{
			cin>>griph[i].u>>griph[i].v>>griph[i].weight>>griph[i].state  ;
		}
		sort(griph,griph+hang,compare);

		for(int i=0;i<hang;i++)
		{
			int xi=find(griph[i].u);
			int yi=find(griph[i].v);
			if(xi!=yi)
			{
				a[xi]=yi;
				if(griph [i].state ==0)//未建
					sum+...