#include <fstream>
#include <vector>
#define MAXN 200000
#define INF 1000000000
using namespace std;
ifstream cin ("apm.in");
ofstream cout ("apm.out");
int dist[MAXN + 10], parent[MAXN + 10];
vector <pair <int, int>> graph[MAXN + 10];
struct ura
{
    int x, y;
};
ura ans[MAXN + 10];
int main()
{
    int n, m;
    cin >> n >> m;
    for (int i = 1; i <= m; i++)
    {
        int x, y, c;
        cin >> x >> y >> c;
        graph[x].push_back({c, y});
        graph[y].push_back({c, x});
    }
    for (int i = 2; i <= n; i++)
        dist[i] = INF;
    dist[1] = -INF;
    int node = 1, costMin = 0 ;
    for (int i = 2; i <= n; i++)
    {
        for (const auto &it : graph[node])
            if (it.first < dist[it.second])
            {
                dist[it.second] = it.first;
                parent[it.second] = node;
            }
        int minDist = INF, nextNode;
        for (int j = 1; j <= n; j++)
            if (dist[j] != -INF && dist[j] < minDist)
            {
                minDist = dist[j];
                nextNode = j;
            }
        costMin = costMin + minDist;
        ans[i - 1] = {parent[nextNode], nextNode};
        dist[nextNode] = -INF;
        node = nextNode;
    }
    cout << costMin << '\n' << n - 1 << '\n';
    for (int i = 1; i < n; i++)
        cout << ans[i].x << ' ' << ans[i].y << '\n';
    return 0;
}