Pagini recente » Cod sursa (job #2885857) | Cod sursa (job #2313796) | Cod sursa (job #2824965) | Cod sursa (job #2385461) | Cod sursa (job #2340899)
#include <fstream>
#include <algorithm>
#define NMAX 200002
#define MMAX 4000002
using namespace std;
ifstream fin("apm.in");
ofstream fout("apm.out");
struct muchie {int x,y,c;};
muchie G[MMAX];
int n,m,cost;
int conex[NMAX];
int a[NMAX];///indicii muchiilor selectate in arbore
///conex[i] este comp conexa din care face parte i
void citire();
void kruskal();
void afisare();
void sortare();
bool compar(muchie a, muchie b)
///returneaza 1(true) daca Muchia a rebuie sa fie inaintea Muchiei b in vectorul sortat
{
return a.c<b.c;
}
int main()
{
citire();
kruskal();
afisare();
return 0;
}
void citire()
{
fin>>n>>m;
int i;
for(i=1;i<=m;i++)
fin>>G[i].x>>G[i].y>>G[i].c;
}
void kruskal()
{
///ordonez muchiile crescator dupa cost
///sortare();
sort(G+1,G+m+1, compar);
int i,nrsel,cx,cy,j;
for(i=1;i<=n;i++)
conex[i]=i;
nrsel=0;
i=1;
while(nrsel<n-1)
{
if(conex[G[i].x]!=conex[G[i].y]) ///nu formeaza ciclu
{
nrsel++;
a[nrsel]=i;
cost+=G[i].c;
///unificam componentele conexe ale extremitatilor
cx=conex[G[i].x];
cy=conex[G[i].y];
for(j=1;j<=n;j++)
if(conex[j]==cy)
conex[j]=cx;
}
i++;
}
}
void sortare()
{
int i,schimb;
muchie aux;
do{
schimb=0;
for(i=1;i<m;i++)
if(G[i].c>G[i+1].c)
{
aux=G[i];
G[i]=G[i+1];
G[i+1]=aux;
schimb=1;
}
}
while(schimb);
}
void afisare()
{
int i;
fout<<cost<<'\n';
fout<<n-1<<'\n';
for(i=1;i<n;i++)
fout<<G[a[i]].x<<" "<<G[a[i]].y<<'\n';
fout.close();
}