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#include <iostream>
#include <fstream>
#include <stdlib.h>
#include <vector>
#include <algorithm>
using namespace std;
typedef struct PAIR{
int muchieX, muchieY, costMuchie;
}PAIR;
PAIR P;
ifstream fin("apm.in");
ofstream fout("apm.out");
int nrNoduri, nrMuchii, costArborePartial, nrMuchiiArborePartial, *vectorTati;
vector <PAIR> muchii;
bool *vizitatMuchii;
int cmp(PAIR X, PAIR Y){
return X.costMuchie < Y.costMuchie;
}
void kruskal(){ //initial toate nodurile sunt izolate, deci apm - ul este creat pe parcurs prin reunirea subarborilor
int nrComponenteConexe = nrNoduri; //nrComponenteConexe reprezinta nr nodurilor grafului
for ( int i = 1; i <= nrNoduri; i++) // ( se pleaca de la ideea de arbore izolat , deci toate nodurile vor fi izolate )
vectorTati[i] = i;
costArborePartial = 0 , nrMuchiiArborePartial = 0;
int lim = muchii.size();
for(int i = 0; i < lim && nrComponenteConexe > 1 ; i++){ //mergem pe fiecare muchie ( cat timp mai avem muchii si nu am parcurs toate nodurile )
if ( vectorTati[muchii[i].muchieX] != vectorTati[muchii[i].muchieY] ){ //daca radacinile difera inseamna ca avem componente conexe diferite
vizitatMuchii[i] = true;
costArborePartial += muchii[i].costMuchie;
nrMuchiiArborePartial++;
int radacinaX = vectorTati[muchii[i].muchieX], radacinaY = vectorTati[muchii[i].muchieY];
for (int j = 1; j <= nrNoduri; j++ ) //unim sub-arborii
if( vectorTati[j] == radacinaY )
vectorTati[j] = radacinaX;
nrComponenteConexe--; //scadem nr componentelor conexe ( efectiv am unit 2 noduri, deci vom scadea nr de componente conexe )
}
}
}
int main(){
if ( !fin ){
cout << "\nEroare la deschiderea fisierului !\n";
exit(-1);
}
fin >> nrNoduri;
vectorTati = NULL;
vectorTati = new int[nrNoduri + 5];
if (!vectorTati){
cout << "\nEroare la alocarea dinamica !\n";
exit(-1);
}
fin >> nrMuchii;
vizitatMuchii = new bool[nrMuchii + 5];
if (!vizitatMuchii){
cout << "\nEroare la alocarea dinamica !\n";
exit(-1);
}
for (int i = 0; i < nrMuchii; i++) {
fin >> P.muchieX >> P.muchieY >> P.costMuchie;
muchii.push_back(P);
vizitatMuchii[i] = false;
}
sort(muchii.begin(),muchii.end(),cmp); //sortez muchiile in ordine descrescatoare dupa cost
kruskal();
fout << costArborePartial << "\n" << nrMuchiiArborePartial << "\n";
for ( int i = 0; i < nrMuchii; i++)
if ( vizitatMuchii[i] )
fout << muchii[i].muchieX << " " << muchii[i].muchieY << endl;
return 0;
}