Cod sursa(job #1040411)

Utilizator DaniEsDani Stetcu DaniEs Data 24 noiembrie 2013 15:01:38
Problema Arbore partial de cost minim Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.01 kb
#include <fstream>
#include <algorithm>
#define NMax 200005
using namespace std;
ifstream f("apm.in");
ofstream g("apm.out");
struct muchie{
    int x, y, c;
    }v[NMax];
int i, n, m, TT[NMax], t, sol[NMax], R[NMax], S;
int cmp(muchie a, muchie b)
{
    return a.c<b.c;
}
int Father(int x)
{
    while(TT[x]!=x)
        x=TT[x];
    return x;
}
void Unite(int x, int y)
{
    if(R[x]<R[y])
        TT[x]=y;
    if(R[y]<R[x])
        TT[y]=x;
    if(R[x]==R[y])
    {
        TT[x]=y;
        R[y]++;
    }
}
int main()
{
    f>>n>>m;
    for(i=1;i<=m;++i)
    {
        f>>v[i].x>>v[i].y>>v[i].c;
    }
    sort(v+1, v+m+1, cmp);
    for(i=1;i<=n;++i)
        TT[i]=i;
    for(i=1;i<=m;++i)
    {
        if(Father(v[i].x)!=Father(v[i].y))
        {
            S+=v[i].c;
            Unite(Father(v[i].x), Father(v[i].y));
            sol[++t]=i;
        }
    }
    g<<S<<'\n'<<n-1<<'\n';
    for(i=1; i<n; i++)
        g<<v[sol[i]].x<<" "<<v[sol[i]].y<<'\n';
    return 0;
}