WA 了12和14点，实在找不出错误。

#include<bits/stdc++.h>
#define ll long long
using namespace std;
struct hhh{
	int s,t,c,col;
}dl[1000010];
ll V,E,need,f[1000010],ans,sum,tot,fina;
bool cmp(hhh x,hhh y){
	if(x.c==y.c) return x.s<y.s;
	return x.c<y.c;
}
int find(int x){
	if(f[x]!=x) return f[x]=find(f[x]);
	return x;
}
void kruskal(){
	sort(dl+1,dl+E+1,cmp);
	for(int i=1;sum<V-1;i++){
		int x=find(dl[i].s),y=find(dl[i].t);
		if(x==y) continue;
		sum++;
		f[y]=x;
		if(dl[i].col==0) tot++;
		ans+=dl[i].c;
	}
}
int main(){
	cin>>V>>E>>need;
	int s,t,c,col;
	for(int i=1;i<=E;i++){
		cin>>dl[i].s>>dl[i].t>>dl[i].c>>dl[i].col;
		dl[i].s++,dl[i].t++;
	}
	int l=-211,r=211;
	while(l<=r){
		int mid=(l+r)/2;
		for(int i=1;i<=E;i++) if(dl[i].col==0) dl[i].c+=mid;
		for(int i=1;i<=V+1;i++) f[i]=i;
		ans=0,sum=0,tot=0;
		kruskal();
		if(tot>=need){
			l=mid+1;
			fina=ans-mid*need;
		}
		else r=mid-1;
		for(int i=1;i<=E;i++) if(dl[i].col==0) dl[i].c-=mid;
	}
	cout<<fina;
	return 0;
}