1143. 联络员最小生成树

Posted 2021-11-01 幽殇默

https://www.acwing.com/problem/content/1145/

#include<bits/stdc++.h>
using namespace std;
const int N=1e5+10;
struct node{int a,b,c;};
bool cmp(node a,node b) {return a.c<b.c;}
vector<node>ve1,ve2;
int p[N],n,m;
int find(int x)
{
    if(x!=p[x]) p[x]=find(p[x]);
    return p[x];
}
int solve()
{
    int res=0;
    for(int i=1;i<=n;i++) p[i]=i;
    for(int i=0;i<ve1.size();i++)
    {
        int a=ve1[i].a,b=ve1[i].b,c=ve1[i].c;
        if(find(a)!=find(b)) p[find(a)]=find(b);
        res+=c;
    }
    sort(ve2.begin(),ve2.end(),cmp);
    for(int i=0;i<ve2.size();i++)
    {
        int a=ve2[i].a,b=ve2[i].b,c=ve2[i].c;
        if(find(a)!=find(b)) p[find(a)]=find(b),res+=c;
    }
    return res;
}
int main(void)
{
    cin>>n>>m;
    for(int i=0;i<m;i++)
    {
        int a,b,c,d; cin>>d>>a>>b>>c;
        if(d==1) ve1.push_back({a,b,c});
        else ve2.push_back({a,b,c});
    }
    cout<<solve()<<endl;
    return 0;
}