关押罪犯 【并查集】
还可以二分答案然后check..
#include<bits/stdc++.h>
using namespace std;
#define N 100010
int n,m;
struct Edge{
int x,y,w;
bool operator < (const Edge& _t)const{
return this->w>_t.w;
}
}e[N];
int fa[N];
int find(int u){
if(u==fa[u])return