#include <iostream>
#include <fstream>
#include <vector>
#include <climits>

using namespace std;
int Q[200001], n, m, d[200001], tata[200001], cost;
vector<pair<int,int>> adj[200001];
ifstream f("apm.in");
ofstream g("apm.out");

void initializare()
{
    for(int i = 1; i <= n; i++) //marcam toate nodurile ca nevizitate
        Q[i] = 1;
    for(int i = 1; i <= n; i++)
    {
        d[i] = INT_MAX;
        tata[i] = 0;
    }
}

int cautare()
{
    int minim = 0;
    int poz = 0;
    for(int i = 1; i <= n; i++)
        if(Q[i] == 1 && d[i] < minim || Q[i] == 1 && poz == 0)
            {poz = i; minim = d[i];}
    if(poz == 0)
        return -1;
    else
        return poz;
}
int main() {
    f >> n >> m;
    for(int i = 0; i < m; i++)
    {
        int x, y, z;
        f >> x >> y >> z;
        adj[x].emplace_back(y, z);
        adj[y].emplace_back(x,z);
    }
    initializare();
    d[1] = 0;
    while(cautare() != -1)
    {
        int u = cautare();
        for(auto x : adj[u])
        {
            int v = x.first;
            if(Q[v] == 1 && x.second < d[v])
            {
                d[v] = x.second;
                tata[v] = u;
            }
        }
        cost += d[u];
        Q[u] = 0;
    }
    g << cost << '\n' << n - 1 << '\n';
    for(int i = 2; i <= n; i++)
        g << i << " " << tata[i]  << '\n';
    return 0;
}