Cod sursa(job #2653014)

Utilizator qThunderStefan Durlanescu qThunder Data 26 septembrie 2020 17:04:05
Problema Arbore partial de cost minim Scor 70
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.13 kb
#include <fstream>
#include <algorithm>
using namespace std;
ifstream fin("apm.in");
ofstream fout("apm.out");
int n,m,a[400004],s,m1;
struct graf
{
    int x,y,c;
};
bool cmp(graf x, graf y)
{
    if(x.c!=y.c)
        return x.c<y.c;
    if(x.x!=y.x)
        return x.x<y.x;
    if(x.y!=y.y)
        return x.y<y.y;
}
graf v[400004],v1[400004];
int arad(int x)
{
    while(a[x]!=0)
        x=a[x];
    return x;
}
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,cmp);
    for(int i=1;i<=m;i++)
    {
        int rx=arad(v[i].x);
        int ry=arad(v[i].y);
        if(rx==ry)
            continue;
        s+=v[i].c;
        if(a[rx]<a[ry])
        {
            a[rx]+=a[ry];
            a[ry]=rx;
            v1[++m1].x=v[i].x;
            v1[m1].y=v[i].y;
        }
        else
        {
            a[ry]+=a[rx];
            a[rx]=ry;
            v1[++m1].x=v[i].x;
            v1[m1].y=v[i].y;
        }
    }
    fout<<s<<"\n"<<m1<<"\n";
    for(int i=1;i<=m1;i++)
        fout<<v1[i].y<<" "<<v1[i].x<<"\n";
    return 0;
}