1141. 局域网最小生成树

Posted 2021-11-01 幽殇默

https://www.acwing.com/problem/content/description/1143/
求这个图的每个联通块内，求一颗最小生成树，相当于求原图的"最小生成深林"

#include<bits/stdc++.h>
using namespace std;
const int N=210;
int n,m,sum;
int p[N];
struct node{int a,b,c;};
bool cmp(node a,node b) {return a.c<b.c;}
vector<node>ve;
int find(int x)
{
    if(x!=p[x]) p[x]=find(p[x]);
    return p[x];
}
int f()
{
    int res=0;
    for(int i=1;i<=n;i++) p[i]=i;
    sort(ve.begin(),ve.end(),cmp);
    for(int i=0;i<ve.size();i++)
    {
        int a=ve[i].a,b=ve[i].b,c=ve[i].c;
        if(find(a)!=find(b))
        {
            p[find(a)]=find(b);
        }
        else res+=c;
    }
    return res;
}
int main(void)
{
    cin>>n>>m;
    for(int i=1;i<=m;i++)
    {
        int a,b,c; cin>>a>>b>>c;
        ve.push_back({a,b,c});
    }
    cout<<f()<<endl;
    return 0;
}