#include <fstream>
#include <stack>
#include <queue>
#include <cmath>
#include <algorithm>
#include <iostream>
#include <set>
#include <cstring>
#include <map>
#include <string>
#include <bitset>
#include <unordered_map>
#include <unordered_set>
#define oo 2000000
#define MOD 1000000007
using namespace std;

ifstream fin("apm.in");
ofstream fout("apm.out");
vector<pair<int, int>>rez;
int r[400005], t[400005], costmax;
int n, m,x,y,c;
struct muchie {
	int x, y, c;
	bool operator<(const muchie m)const
	{
		return c < m.c;
	}
}a[400005];

void Union(int x, int y)
{
	if (r[x] > r[y])
		t[x] = y;
	else
	{
		t[x] = y;
		if (r[x] == r[y])
			r[y]++;
	}
}
int find(int x)
{
	if (t[x] == 0)
		return x;
	int y = find(t[x]);
	t[x] = y;
	return y;
}
int main()
{
	fin >> n >> m;
	for (int i = 1; i <= m; i++)
	{
		fin >> a[i].x >> a[i].y >> a[i].c;
	}
	sort(a + 1, a + m + 1);
	for (int i = 1; i <= m; i++)
	{
		int x = find(a[i].x);
		int y = find(a[i].y);
		if (x != y)
		{
			Union(x, y);
			costmax += a[i].c;
			rez.push_back({ a[i].y,a[i].x });
		}
	}
	fout << costmax<<endl;
	fout << rez.size() << endl;
	for (int i = 0; i < rez.size(); i++)
		fout << rez[i].first << " " << rez[i].second << endl;
}