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

using namespace std;

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

const int NMAX = 200000 + 1;
const int MMAX = 400000 + 1;

int n, m;
int t[NMAX + 1];
int h[NMAX + 1];

bool in_apm[MMAX];

pair < int, pair <int, int> > muchii[MMAX];

void citeste() {
	f >> n >> m;

	for (int i = 1; i <= m; i++) {
		f >> muchii[i].second.first >> muchii[i].second.second >> muchii[i].first;
	}
}

void init() {
	for (int i = 1; i <= n; i++) {
		t[i] = 0;
		h[i] = 1;
	}
}

int get_radacina(int a) {
	if (t[a] == 0) return a;
	t[a] = get_radacina(t[a]);
	return t[a];
}

bool query(int a, int b) {
	return get_radacina(a) == get_radacina(b);
}

void unite(int a, int b) {
	int ra = get_radacina(a);
	int rb = get_radacina(b);

	if (ra == rb) return;

	if (h[ra] >= h[rb]) {
		t[rb] = ra;
		h[ra] = max(h[ra], h[rb] + 1);
	}
	else {
		t[ra] = rb;
		h[rb] = max(h[rb], h[ra] + 1);
	}
}

void rezolva() {
	sort(muchii + 1, muchii + m + 1);

	int cost_total = 0;
	int muchii_apm = 0;

	for (int i = 1; i <= m; i++) {
		int a = muchii[i].second.first;
		int b = muchii[i].second.second;

		if (query(a, b)) continue;
		unite(a, b);
		cost_total += muchii[i].first;
		muchii_apm++;
		in_apm[i] = true;
	}

	g << cost_total << '\n';
	g << muchii_apm << '\n';
	for (int i = 1; i <= m; i++) {
		if (!in_apm[i]) continue;
		g << muchii[i].second.first << ' ' << muchii[i].second.second << '\n';
	}
}

int main() {
	citeste();
	init();
	rezolva();
	return 0;
}