Cod sursa(job #2691616)

Utilizator popabogdanPopa Bogdan Ioan popabogdan Data 29 decembrie 2020 13:48:16
Problema Arbore partial de cost minim Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.18 kb
#include <bits/stdc++.h>

#define Nmax 200002

using namespace std;

ifstream fin("apm.in");
ofstream fout("apm.out");

struct edge
{
    int x, y, c;
};
vector <edge> E;
vector <edge> S;

int T[Nmax];
int L[Nmax];
int N, M;
int i;

int find(int node)
{
    if(node == T[node])
        return node;
    return T[node] = find(T[node]);
}

void unite(int a, int b)
{
    a = find(a);
    b = find(b);
    if(L[a] < L[b])
        swap(a, b);
    L[a] += L[b];
    T[b] = a;
}

bool qx(edge a, edge b)
{
    return a.c < b.c;
}

int main()
{
    fin >> N >> M;
    for(i = 1; i <= M; i++)
    {
        int x, y, c;
        fin >> x >> y >> c;
        E.push_back({x, y, c});
    }
    for(i = 1; i <= N; i++)
    {
        T[i] = i;
        L[i] = 1;
    }
    int sol = 0;
    sort(E.begin(), E.end(), qx);
    for(i = 0; i < M; i++)
        if(find(E[i].x) != find(E[i].y))
        {
            sol += E[i].c;
            unite(E[i].x, E[i].y);
            S.push_back(E[i]);
        }
    fout << sol << "\n";
    fout << S.size() << "\n";
    for(i = 0; i < S.size(); i++)
        fout << S[i].x << " " << S[i].y << "\n";
    return 0;
}