bzoj2654: tree

#include<cstdio>
#include<cstring>
#include<iostream>
#include<algorithm>
using namespace std;
#define rep(i,n) for(int i=1;i<=n;i++)
#define clr(x,c) memset(x,c,sizeof(x))
int read(){
	int x=0;char c=getchar();
	while(!isdigit(c)) c=getchar();
	while(isdigit(c)) x=x*10+c-‘0‘,c=getchar();
	return x;
}
const int nmax=50005;
const int maxn=100005;
const int inf=0x7f7f7f7f;
struct edge{
	int from,to,dist,op;
	bool operator<(const edge &rhs) const{
	  return dist<rhs.dist||(dist==rhs.dist&&op<rhs.op);}
};
edge edges[maxn];
int fa[nmax],n,m,need;
int find(int x){
	return fa[x]==x?x:fa[x]=find(fa[x]);
}
int check(int x){
	rep(i,n) fa[i]=i;
	int ans=0,cnt=0;
	rep(i,m) if(!edges[i].op) edges[i].dist+=x;
	sort(edges+1,edges+m+1);
	rep(i,m){
		int ta=find(edges[i].from);int tb=find(edges[i].to);
		if(ta!=tb) {
			fa[ta]=tb;ans+=edges[i].dist;
			if(!edges[i].op) cnt++;
		}
	}
	rep(i,m) if(!edges[i].op) edges[i].dist-=x;
	return cnt>=need?ans:-1;
}
void work(){
	int ans,l=-300,r=300;
	while(l<=r){
		int mid=(l+r)>>1;
		int tmp=check(mid);
		if(tmp!=-1) {
			ans=tmp-need*mid;l=mid+1;
		}else r=mid-1;
	}
	printf("%d\n",ans);
}
int main(){
	n=read(),m=read(),need=read();
	rep(i,m){
		edge &oo=edges[i];
		oo.from=read()+1,oo.to=read()+1,oo.dist=read(),oo.op=read();
	}
	work();return 0;
}