Cod sursa(job #3339885)

Utilizator popescumalinaPopescu Malina popescumalina Data 10 februarie 2026 18:16:31
Problema Arbore partial de cost minim Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.16 kb
#include <iostream>
#include <fstream>
#include <algorithm>
using namespace std;
const int NMAX = 200000;

struct muchie
{
    int i, j, c;
};

int n, m,
    cost;
muchie M[400001];
int CC[NMAX + 1];
int NrM[NMAX],
    nm;

ifstream f("apm.in");
ofstream g("apm.out");

void citire()
{
    f >> n >> m;
    for(int k = 1; k <= m; k++)
        f >> M[k].i >> M[k].j >> M[k].c;
}

void afis()
{
    g << cost << '\n' << nm << '\n';
    for(int i = 1; i <= nm; i++)
    {
        int k = NrM[i];
        g << M[k].i << ' ' << M[k].j << '\n';
    }
}

bool comp(const muchie &a, const muchie &b)
{
    return a.c < b.c;
}

int Find(int i)
{
    if(CC[i] == 0)
        return i;
    return CC[i] = Find(CC[i]);
}

void Kruskal()
{
    sort(M + 1, M + m + 1, comp);
    for(int i = 1; i <= m; i++)
    {
        int ci = Find(M[i].i),
            cj = Find(M[i].j);
        if(ci != cj)
        {
            cost += M[i].c;
            CC[ci] = cj;
            NrM[++nm] = i;
            if(nm == n - 1)
                break;
        }
    }
}

int main()
{
    citire();
    Kruskal();
    afis();
    return 0;
}