Cod sursa(job #1935710)

Utilizator Horia14Horia Banciu Horia14 Data 22 martie 2017 16:51:23
Problema Arbore partial de cost minim Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.41 kb
#include<cstdio>
#include<algorithm>
#define M_MAX 400000
#define N_MAX 200000
using namespace std;

struct muchie
{
    int x, y, cost;
};

struct Vector
{
    int x, y;
};

muchie v[M_MAX+1];
Vector s[M_MAX];
int p[N_MAX+1], n, m, cost, nrm;

bool cmp(muchie a, muchie b)
{
    if(a.cost < b.cost) return true;
    return false;
}

void Read()
{
    FILE *fin = fopen("apm.in","r");
    fscanf(fin,"%d%d",&n,&m);
    for(int i=0; i<m; i++)
        fscanf(fin,"%d%d%d",&v[i].x, &v[i].y, &v[i].cost);
    fclose(fin);
}

void Init()
{
    for(int i=1; i<=n; i++)
        p[i] = i;
}

int Find(int x)
{
    int r = x, aux;
    while(p[r] != r)
        r = p[r];
    while(p[x] != r)
    {
        aux = p[x];
        p[x] = r;
        x = aux;
    }
    return r;
}

void APM()
{
    int i, RootX, RootY;
    for(i=0; i<m; i++)
    {
        RootX = Find(v[i].x);
        RootY = Find(v[i].y);
        if(RootX != RootY)
        {
            p[RootX] = RootY;
            cost += v[i].cost;
            s[nrm].x = v[i].x;
            s[nrm++].y = v[i].y;
        }
    }
}

void Write()
{
    FILE *fout = fopen("apm.out","w");
    fprintf(fout,"%d\n%d\n",cost,nrm);
    for(int i=0; i<nrm; i++)
        fprintf(fout,"%d %d\n",s[i].x,s[i].y);
    fclose(fout);
}

int main()
{
    Read();
    Init();
    sort(v,v+m,cmp);
    APM();
    Write();
}