Cod sursa(job #2545483)

Utilizator AlexAlAxAxelAlAx AlAx AlexAlAxAxel Data 13 februarie 2020 10:24:52
Problema Arbore partial de cost minim Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.32 kb
#include <fstream>
#include <algorithm>
using namespace std;
ifstream f("apm.in");
ofstream g("apm.out");

const int nlim=400001;
int n,m,tt[nlim],rg[nlim],z=0,total=0;
pair <int, int> P[nlim];

struct muchie
{
    int a,b,cost;
}v[nlim];

int compara(muchie a, muchie b)
{
    return a.cost<b.cost;
}

void unire(int x, int y)
{
    if(rg[x]<rg[y])
        tt[x]=y;
    if(rg[x]>rg[y])
        tt[y]=x;
    if(rg[x]==rg[y])
    {
        tt[x]=y;
        rg[y]++;
    }
}

int tata(int x)
{
    while(tt[x]!=x)
        x=tt[x];
    return x;
}

void citire()
{
    f>>n>>m;
    for(int i=1;i<=m;i++)
        f>>v[i].a>>v[i].b>>v[i].cost;
    sort(v+1,v+m+1,compara);
    for(int i=1;i<=m;i++)
    {
        tt[i]=i;
        rg[i]=1;
    }
}

void rezolva()
{
    for(int i=1;i<=m;i++)
    {
        int tatal_x=tata(v[i].a);
        int tatal_y=tata(v[i].b);
        if(tatal_x!=tatal_y)
        {
            unire(tatal_x,tatal_y);
            z++;
            P[z].first=v[i].a;
            P[z].second=v[i].b;
            total=total+v[i].cost;
        }
    }
}

void afisare()
{
    g<<total<<'\n'<<z<<'\n';
    for(int i=1;i<=z;i++)
        g<<P[i].first<<" "<<P[i].second<<'\n';
}

int main()
{
    citire();
    rezolva();
    afisare();
    return 0;
}