#include <iostream>
#include <fstream>
#include <algorithm>
using namespace std;

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

const int MMAX = 4e5 + 5;
const int NMAX = 1e5 + 5;

struct edge {
    int x, y, c;
};
edge e[MMAX];
int h[NMAX], dad[NMAX], cnt, ans[NMAX], sum;

bool cmp(const edge &a, const edge &b) {
    return a.c < b.c;
}

void Union(int x, int y) {
    if(h[x] > h[y]) {
        dad[y] = x;
    } else {
        dad[x] = y;
        if(h[x] == h[y]) {
            h[y]++;
        }
    }
}

int Find(int x) {
    int root = x;
    while(dad[root] != root) {
        root = dad[root];
    }
    int y = x;
    while(y != root) {
        int t = dad[y];
        dad[y] = root;
        y = t;
    }
    return root;
}

int main()
{
    int n, m;
    f >> n >> m;
    for(int i = 1; i <= m; i++) {
        f >> e[i].x >> e[i].y >> e[i].c;
    }
    sort(e + 1, e + m + 1, cmp);
    for(int i = 1; i <= n; i++) {
        dad[i] = i;
        h[i] = 1;
    }
    for(int i = 1; i <= m && cnt < n - 1; i++) {
        int p = Find(e[i].x);
        int q = Find(e[i].y);
        if(p != q) {
            cnt++;
            sum += e[i].c;
            ans[cnt] = i;
            Union(p, q);
        }
    }
    g << sum << '\n';
    g << n - 1 << '\n';
    for(int i = 1; i <= n - 1; i++) {
        g << e[ans[i]].x << ' ' << e[ans[i]].y << '\n';
    }
    return 0;
}