Cod sursa(job #2572228)

Utilizator Vlad_NituNitu Vlad-Petru Vlad_Nitu Data 5 martie 2020 12:11:27
Problema Arbore partial de cost minim Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.5 kb
#include <bits/stdc++.h>
#define NMAX 200005
#define MMAX 400005
using namespace std;
ifstream f ("apm.in") ;
ofstream g ("apm.out") ;
int T[NMAX] , h[NMAX] ;
struct solutie
{
    int st;
    int dr;
}v[NMAX];
int N , M , x ,y ,cost = 0;
int cnt = 0 , k = 0 ;
struct didi
{
    int a;
    int b;
    int c;
}mch[MMAX];
bool cmp (didi a , didi b)
{
    return (a.c < b.c) ;
}
int TATA (int x)
{
    if (x != T[x]) return TATA(T[x]) ;
    return x;
}
int muchie (int x , int y)
{
    int r1 = TATA(x) ;
    int r2 = TATA(y) ;

    if (r1 == r2) return 0 ;
    else
    {
        if (h[r1] < h[r2]) T[r1] = r2;
        else if (h[r1] > h[r2]) T[r2] = r1;
        else
        {
            T[r2] = r1;
            h[r1] ++ ;
        }

        return 1;
    }
}
void KRUSKAL()
{
     k = 1;
    while (cnt < N - 1 && k <= M)
    {
        x = mch[k].a;
        y = mch[k].b;
        if (muchie(x,y))
        {
            cost += mch[k].c ;
            cnt ++ ;
            v[cnt].st = x;
            v[cnt].dr = y;
        }

        k ++ ;
    }
}
int main()
{
    f >> N >> M ;
    for (int i = 1 ; i <= M ; ++i)
        f >> mch[i].a >> mch[i].b >> mch[i].c;

    sort(mch+1,mch+M+1,cmp) ;
    for (int i = 1; i <= N ; ++i) T[i] = i , h[i] = 1;

    KRUSKAL();

    g << cost << '\n' ;
    g << N - 1 << '\n' ;
    for (int i = 1 ; i <= cnt ; ++i)
        g << v[i].st <<  ' ' << v[i].dr << '\n' ;

    f.close();
    g.close();
    return 0 ;
}