#include <iostream>
#include <fstream>
#include <algorithm>

using namespace std;



const int NMAX = 200000;
int p[NMAX + 1], sz[NMAX + 1];

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

void Union(int x, int y) {
    x = Find(x);
    y = Find(y);
    if (sz[x] > sz[y]) {
        p[y] = x;
        sz[x] += sz[y];
    }
    else {
        p[x] = y;
        sz[y] += sz[x];
    }
}

struct muchie{
    int x,y,c;
};
muchie v[400005], r[200005];

bool cmp (muchie a, muchie b){
    return a.c < b.c;
}

int main() {

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

    int n, m;
    fin >> n >> m;

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

    for (int i = 1; i <= m; i++) {
        fin >> v[i].x >> v[i].y >> v[i].c;
    }

    sort(v + 1, v + m + 1, cmp);

    int sum = 0;
    int nr = 0;
    for(int i = 1; i <= m; i++){
        if(Find(v[i].x) != Find(v[i].y)){
            nr++;
            r[nr] = v[i];
            sum += v[i].c;
            Union(v[i].x,v[i].y);
        }
    }

    fout << sum << '\n';
    //afis nr si muchi
    fout << nr << '\n';
    for (int i = 1; i <= nr; i++) {
        fout << r[i].x << ' ' << r[i].y << '\n';
    }

    return 0;
}