Cod sursa(job #3203022)

Utilizator arinaststsArina Stroe arinaststs Data 12 februarie 2024 22:11:29
Problema Arbore partial de cost minim Scor 80
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.25 kb
#include <fstream>
#include <vector>
#include <algorithm>
using namespace std;
ifstream fin("apm.in");
ofstream fout("apm.out");
int n, m, sum, nrmuchii;
struct muchiis{
    int i, j, cost;
}muchii[400001];
vector<int> G[200001];
void citire()
{
    fin>>n>>m;
    for(int i=0; i<m; i++)
    {
        int x, y, c;
        fin>>x>>y>>c;
        muchii[i].i=x, muchii[i].j=y, muchii[i].cost=c;
    }
}
bool cst_srt(muchiis a, muchiis b)
{
    if(a.cost<b.cost)
        return true;
    return false;
}
int root[200001];
int rad(int k)
{
    if(root[k]==k)
        return k;
    int rez=rad(root[k]);
    root[k]=rez;
    return rez;
}
void unire(int ra, int rb)
{
    for(int i=1; i<=n; i++)
        if(root[i]==rb)
            root[i]=ra;
}
void kruskal()
{
    sort(muchii, muchii+m, cst_srt);
    for(int i=1; i<=n; i++)
        root[i]=i;
    for(int i=0; i<m; i++)
    {
        int rx=rad(muchii[i].i), ry=rad(muchii[i].j);
        if(rx==ry)
            continue;
        unire(rx, ry);
        G[muchii[i].i].push_back(muchii[i].j);
        sum+=muchii[i].cost;
        nrmuchii++;
    }
}
int main()
{
    citire();
    kruskal();
    fout<<sum<<'\n'<<nrmuchii<<'\n';
    for(int i=1; i<=n; i++)
        for(auto j: G[i])
            fout<<i<<" "<<j<<'\n';
    return 0;
}