Cod sursa(job #2686367)

Utilizator Asgari_ArminArmin Asgari Asgari_Armin Data 18 decembrie 2020 23:55:11
Problema Arbore partial de cost minim Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.1 kb
#include <bits/stdc++.h>
#pragma GCC optimize("Ofast")
#pragma GCC optimize("O3")

using namespace std;

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

const int NMAX = 2e5;
const int MMAX = 4e5;
struct lol {
  int a, b, c;
  bool operator < ( const lol &shit ) const {
    return c < shit.c;
  }
};
lol v[MMAX + 1];
int sef[NMAX + 1];
vector <pair<int, int>> sol;

int myfind( int x ){
  if( sef[x] == x )
    return x;
  return sef[x] = myfind(sef[x]);
}

void myunite( int x, int y ){
  int sefx = myfind(x), sefy = myfind(y);
  if( sefx != sefy )
    sef[sefy] = sefx;
}

int main() {
  int n, m, i, sum;
  fin >> n >> m;
  for( i = 0; i < m; ++i )
    fin >> v[i].a >> v[i].b >> v[i].c;
  for( i = 1; i <= n; ++i )
    sef[i] = i;
  sort( v, v + m );
  sum = 0;
  for( i = 0; i < m; ++i )
    if( myfind(v[i].a) != myfind(v[i].b) ){
      sum += v[i].c;
      sol.push_back({v[i].a, v[i].b});
      myunite(v[i].a, v[i].b);
    }
  fout << sum << "\n" << sol.size() << "\n";
  for( auto it : sol )
    fout << it.first << " " << it.second << "\n";
  return 0;
}