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

int n, m;
int k, cost;
int t[400001], h[400001];

struct muchii
{
	int x, y, c;
} a[400001];

vector< pair<int , int> > M;

bool Pred(muchii a, muchii b)
{
	return a.c < b.c;
}

void Read();
void APM();
void Write();
int Find(int );
void Union(int, int);

int main()
{
	Read();
	APM();
	Write();
	return 0;
}

void Read()
{
	ifstream fin("apm.in");
	fin >> n >> m;
	M.resize(m+1);
	
	int x, y, c;
	for(int i = 1; i <= m; ++i)
	{
		if( i <= n ) t[i] = i;
		fin >> x >> y >> c;
		a[i].x = x;
		a[i].y = y;
		a[i].c = c;
	}
}

void APM()
{
	sort(a+1, a+m+1, Pred);
	
	for(int i = 1; i <= m && k < n-1; ++i)
	{
		int v1 = Find(a[i].x);
		int v2 = Find(a[i].y);
		
		if( v1 != v2 )
		{
			cost += a[i].c;
			M[++k] = make_pair(a[i].x, a[i].y);
			Union(v1, v2);
		}
	}
}

int Find(int x)
{
	if( x != t[x])
		t[x] = Find(t[x]);
	return t[x];
}

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

void Write()
{
	ofstream fout("apm.out");
	fout << cost <<"\n" << k << "\n";
	
	for(int i = 1; i <= n-1; ++i)
		fout << M[i].first << " "<<M[i].second << "\n";
	fout.close();
}