Cod sursa(job #1260506)

Utilizator binicBinica Nicolae binic Data 11 noiembrie 2014 13:04:29
Problema Arbore partial de cost minim Scor 50
Compilator cpp Status done
Runda Arhiva educationala Marime 1.17 kb
#include<cstdio>
#include<algorithm>
using namespace std;
int n,m,i,x,y,c,z,x1,yy,t,j,b[200004],mch[200004],h[200004];
long long s;
struct nod
{
    int x,y;
    short c;
}a[400003];
int tata(int x)
{
    if(x==b[x])return x;
    else return tata(b[x]);
}
bool cmp(nod a, nod b)
{
    if(a.c>b.c)return 0;
    return 1;
}
int main()
{
    freopen("apm.in","r",stdin);
    freopen("apm.out","w",stdout);
    scanf("%d %d",&n,&m);
    for(i=1;i<=m;i++)
    {
        scanf("%d %d %d",&x,&y,&c);
        if(x<y){a[i].x=x;a[i].y=y;}
        else {a[i].x=y;a[i].y=x;}
        a[i].c=c;
    }
    for(i=1;i<=n;i++){b[i]=i;h[i]=1;}
    sort(a+1,a+m+1,cmp);
    for(i=1;i<=m;i++)
    {
        x=a[i].x;
        y=a[i].y;
        c=a[i].c;
        x1=tata(x);
        yy=tata(y);
        if(x1!=yy)
        {
            if(h[x1]<h[yy]) b[x1]=yy;
            else b[yy]=x1;
            if(h[x1]==h[yy]) h[yy]++;
            s=s+c;
            z++;
            mch[z]=i;
            if(z==n-1)break;
        }
    }
    printf("%d\n",s);
    printf("%d\n",z);
    for(i=1;i<=z;i++)
        printf("%d %d\n",a[mch[i]].x,a[mch[i]].y);
    return 0;
}