Cod sursa(job #3361115)

Utilizator adimiclaus15Miclaus Adrian Stefan adimiclaus15 Data 20 iulie 2026 15:46:39
Problema Arbore partial de cost minim Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.34 kb

#include <bits/stdc++.h>
using namespace std;

const int NMAX = 2e5;
const int MMAX = 4e5;
int p[NMAX + 1], sz[NMAX + 1];

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

muchie v[MMAX + 1], a[MMAX + 1];

int find(int x) {
    int r = x;
    while(r != p[r]) {
        r = p[r];
    }
    int y = x;
    while(y != r) {
        int t = p[y];
        p[y] = r;
        y = t;
    }
    return r;
}

void join(int x, int y) {
    int px = find(x);
    int py = find(y);
    if(sz[px] > sz[py]) {
        swap(px, py);
    }
    p[px] = py;
    sz[py] += sz[px];
    sz[px] = 0;
}

int query(int x, int y) {
    return find(x) == find(y);
}

bool cmp(muchie m1, muchie m2) {
    return m1.c < m2.c;
}

int main() {
    ifstream cin("apm.in");
    ofstream cout("apm.out");
	int n, m;
    cin >> n >> m;
    for(int i = 1; i <= n; i++) {
        p[i] = i;
        sz[i] = 1;
    }
    for(int i = 1; i <= m; i++) {
        cin >> v[i].x >> v[i].y >> v[i].c;
    }
    sort(v + 1, v + m + 1, cmp);
    int cnt = 0;
    int sol = 0;
    for(int i = 1; i <= m && cnt < n - 1; i++) {
        if(query(v[i].x, v[i].y) == 0) {
            cnt++;
            sol += v[i].c;
            join(v[i].x, v[i].y);
            a[cnt] = v[i];
        }
    }
    cout << sol << '\n';
    cout << cnt << '\n';
    for(int i = 1; i <= cnt; i++) {
        cout << a[i].x << ' ' << a[i].y << '\n';
    }
}