Cod sursa(job #2677516)

Utilizator ANNOnymousMihaila Stefan-Alexandru ANNOnymous Data 26 noiembrie 2020 18:24:13
Problema Arbore partial de cost minim Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.07 kb
#include <bits/stdc++.h>

using namespace std;

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

const int Nmax=400005;

int n, m, Total, T[Nmax], cnt;

struct Muchie
{
    int x, y, cost;
}G[Nmax];

Muchie A[Nmax];

bool compare(Muchie a, Muchie b)
{
    return a.cost < b.cost;
}

void citire()
{
    fin>>n>>m;
    for(int i=1; i<=m; i++)
    {
        fin>>G[i].x>>G[i].y>>G[i].cost;
    }
    for(int i=1; i<=n; i++)
        T[i]=i;
    sort(G+1, G+m+1, compare);
}

int leaga(int a, int b)
{
    T[a]=T[b];
}

int radacina(int a)
{
    if(a==T[a]) return a;
    else return T[a]=radacina(T[a]);
}

void Kruskal()
{
    int r1, r2;
    for(int i=1; i<=m; i++)
    {
        r1= radacina(G[i].x);
        r2= radacina(G[i].y);
        if(r1!=r2)
        {
            Total+=G[i].cost;
            A[++cnt]=G[i];
            leaga(r1, r2);
        }
    }
}

int main()
{
    citire();
    Kruskal();
    fout<<Total<<'\n';
    fout<<cnt<<'\n';
    for(int i=1; i<n; i++)
        fout<<A[i].y<<" "<<A[i].x<<'\n';
}