#include <iostream>
#include <vector>
#include <queue>
#include <fstream>

using namespace std;

ifstream fin("apm.in");
ofstream fout("apm.out");

void primsAlgorithm(vector<vector<pair<int, int>>>& graph, int n, int start = 1) 
{
    priority_queue<pair<int, int>, vector<pair<int, int>>, greater<pair<int, int>>> pq;

    vector<bool> visited(n + 1, false);
    vector<int> key(n + 1, 1e9);
    vector<int> parent(n + 1, -1);

    key[start] = 0;
    pq.emplace(0, start);

    int total_cost = 0;

    while (!pq.empty()) 
    {
        int node = pq.top().second;
        int weight = pq.top().first;
        pq.pop();

        if (visited[node]) 
            continue;

        visited[node] = true;
        total_cost += weight;

        for (auto& neighbor : graph[node]) 
        {
            int adjNode = neighbor.first;
            int edgeWeight = neighbor.second;

            if (!visited[adjNode] && edgeWeight < key[adjNode]) 
            {
                key[adjNode] = edgeWeight;
                parent[adjNode] = node;
                pq.emplace(edgeWeight, adjNode);
            }
        }
    }

    fout << total_cost << '\n';
    vector<pair<int, int>> mst_edges;
    
    for (int i = 1; i <= n; ++i) 
    {
        if (parent[i] != -1) 
            mst_edges.emplace_back(parent[i], i);
    }

    fout << mst_edges.size() << '\n';
    for (const auto& edge : mst_edges) 
    {
        fout << edge.first << ' ' << edge.second << '\n';
    }
}

int main() 
{
    int n, m;
    fin >> n >> m;

    vector<vector<pair<int, int>>> graph(n + 1);

    for (int i = 0; i < m; i++) 
    {
        int a, b, c;
        fin >> a >> b >> c;
        graph[a].emplace_back(b, c);
        graph[b].emplace_back(a, c);
    }

    primsAlgorithm(graph, n);

    return 0;
}