Cod sursa(job #1299653)

Utilizator SagunistuStrimbu Alexandru Sagunistu Data 23 decembrie 2014 19:35:38
Problema Arbore partial de cost minim Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.18 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <algorithm>

#define nmax 200005

using namespace std;

ifstream fin("apm.in");
ofstream fout("apm.out");

pair<int,pair<int,int> >g[2*nmax];
int n,m,cost,t[nmax];
vector<pair<int,int> >v;

void citire()
{
    int x,y,c;
    fin>>n>>m;
    for(int i=1;i<=m;i++)
    {
        fin>>x>>y>>c;
        g[i]=make_pair(c,make_pair(x,y));
    }
    for(int i=1;i<=n;i++)
        t[i]=i;
}

int tata(int k)
{
    if(t[k]==k)
        return k;
    t[k]=tata(t[k]);
        return t[k];
}

void adaug(int a,int b)
{
    t[t[a]]=t[b];
    v.push_back(make_pair(a,b));
}

void kruskal()
{
    int a,b;
    for(int i=1;i<=m;i++)
    {
        a=g[i].second.first;
        b=g[i].second.second;
        if(tata(a)==tata(b))
            continue;
        adaug(a,b);
        cost+=g[i].first;
    }
}

void afisare()
{
    int nr=v.size();
    fout<<cost<<"\n"<<nr<<"\n";
    for(vector<pair<int,int> >::iterator ii=v.begin();ii!=v.end();++ii)
        fout<<ii->first<<" "<<ii->second<<"\n";
}

int main()
{
    citire();
    sort(g+1,g+m+1);
    kruskal();
    afisare();
    return 0;
}