最小生成树 Kruskal

#include<iostream>
#include<cstdio>
#include<cstring>
#include<cstdlib>
#include<cmath>
#include<algorithm>
using namespace std;
int n,m,jdg[5001],cnt,ans;
struct uio{
    int from,to,que;
}road[200001];
int find(int x)
{
    if(x==jdg[x])
        return x;
    return jdg[x]=find(jdg[x]);
}
bool cmp(uio x,uio y)
{
    return x.que<y.que;
}
int main()
{
    cin>>n>>m;
    for(int i=1;i<=n;i++)
        jdg[i]=i;
    for(int i=1;i<=m;i++)
        cin>>road[i].from>>road[i].to>>road[i].que;
    sort(road+1,road+1+m,cmp);
    for(int i=1;i<=m;i++)
    {
        int x=find(road[i].from);
        int y=find(road[i].to);
        if(x!=y)
        {
            ans+=road[i].que;
            cnt++;
            jdg[x]=y;
        }
        if(cnt==n-1)
            break;
    }
    cout<<ans<<endl;
    return 0;
}