Cod sursa(job #2686459)

Utilizator SoranaAureliaCatrina Sorana SoranaAurelia Data 19 decembrie 2020 10:51:30
Problema Arbore partial de cost minim Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.2 kb
#include <fstream>
#include <vector>
#include <queue>
#define NMAX 200005
using namespace std;

ifstream f("apm.in");
ofstream g("apm.out");

int n, m;
int x, y, c, sum;
int viz[NMAX], nrmuchii;


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

    bool operator<(const muchie &other) const {
        if(cost!=other.cost)
            return cost>other.cost;
        return y>other.y;
    }
};
muchie sol[NMAX];
vector<muchie> graph[NMAX];
priority_queue<muchie> Q;

void solve(){
    for(int i=2; i<=n; i++){
        muchie minima = Q.top();
        while(viz[minima.y] == 1){
            Q.pop();
            minima = Q.top();
        }

        sol[nrmuchii++] = {minima.x, minima.y};
        viz[minima.y]=1;

        sum =sum + minima.cost;
        for(auto &v:graph[minima.y])
            Q.push(v);
    }
}
int main()
{
    f>>n>>m;
    for(int i=1; i<=m; i++){
        f>>x>>y>>c;
        graph[x].push_back({x, y, c});
        graph[y].push_back({y, x, c});
    }
    for(auto &v:graph[1])
        Q.push(v);
    viz[1] = 1;
    solve();
    g<<sum<<'\n'<<n-1<<'\n';
    for(int i=0; i<n-1; i++)
        g<<sol[i].x<<" "<<sol[i].y<<'\n';
    return 0;
}