Cod sursa(job #2661386)

Utilizator NashikAndrei Feodorov Nashik Data 21 octombrie 2020 21:51:22
Problema Arbore partial de cost minim Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.37 kb
//#include <iostream>
#include <fstream>
#include <algorithm>
using namespace std;
ifstream cin("apm.in");
ofstream cout("apm.out");
pair<int,pair<int,int> > muchie[400005];
int t[200005],sz[200005],sum=0,sol[200005];
bool mysort(pair<int,pair<int,int> > a,pair<int,pair<int,int> > b){
    return a.second.second<b.second.second;
}
int daddy(int a){
    if(t[a]==a)
        return a;
    t[a]=daddy(t[a]);
    return t[a];
}
bool same(int a,int b){
    a=daddy(a);
    b=daddy(b);
    return (a==b);
}
void unite(int a,int b){
    a=daddy(a);
    b=daddy(b);
    if(sz[a]<sz[b]){
        t[a]=b;
        sz[b]+=sz[a];
    }
    else{
        t[b]=a;
        sz[a]+=sz[b];
    }
}
int main()
{
    int n,m;
    cin>>n>>m;
    for(int i=1;i<=m;i++){
        cin>>muchie[i].first>>muchie[i].second.first>>muchie[i].second.second;
    }
    sort(muchie+1,muchie+m+1,mysort);
    for(int i=1;i<=n;i++){
        sz[i]=1;
        t[i]=i;
    }
    int cnt=0;
    for(int i=1;i<=m;i++){
        if(same(muchie[i].first,muchie[i].second.first)==true)
            continue;
        sum+=muchie[i].second.second;
        unite(muchie[i].first,muchie[i].second.first);
        sol[++cnt]=i;
    }
    cout<<sum<<"\n"<<n-1<<"\n";
    for(int i=1;i<n;i++){
        cout<<muchie[sol[i]].first<<" "<<muchie[sol[i]].second.first<<"\n";
    }
    return 0;
}