Cod sursa(job #1609299)

Utilizator CalinSpiridonSpiridon Calin CalinSpiridon Data 22 februarie 2016 18:38:56
Problema Arbore partial de cost minim Scor 10
Compilator cpp Status done
Runda Arhiva educationala Marime 1 kb
#include <fstream>
#include <algorithm>
using namespace std;

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

struct mk{
    int x, y, c;
};
mk v[400010];

bool test(mk a, mk b){
    return a.c<b.c;
}

int n, m, x, y, c, t;
int a[200010], s[200010];


int grupa(int i)
{
    if (a[i] == i) return i;
    a[i] = grupa(a[i]);
    return a[i];
}

void reuniune(int i,int j)
{
    a[grupa(i)] = grupa(j);
}



int main(){
    fin>>n>>m;
    for(int i=1;i<=m;++i){
        fin>>v[i].x>>v[i].y>>v[i].c;
    }
    sort(v+1, v+m+1, test);
    for(int i=1;i<=n;++i) a[i]=i;
    int k=0;
    int p=1;
    while(k<n-1){
        if(a[v[p].x]!=a[v[p].y]){
            ++k;
            s[k]=p;
            t+=v[p].c;
            int w1=a[v[p].x];
            int w2=a[v[p].y];
            reuniune(w1, w2);
        }
        ++p;
    }
    fout<<t<<'\n';
    fout<<n-1<<'\n';
    for(int i=1;i<=k;++i){
        fout<<v[s[i]].x<<' '<<v[s[i]].y<<'\n';
    }



    return 0;
}