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

using namespace std;

#define MAXN 200010

ifstream f("apm.in");
ofstream g("apm.out");

vector<pair<int, int>> G[MAXN];
priority_queue<pair<int, pair<int, int>>> PQ;
vector<pair<int, int>> muchii;
int n, m, nr, x, y, c, total;
int viz[MAXN];

int main()
{
    f >> n >> m;

    while (m--) {
        f >> x >> y >> c;
        G[x].push_back({y, c});
        G[y].push_back({x, c});
    }

    for (auto it:G[1]){
        PQ.push({-it.second, {it.first, 1}});
    }
    viz[1] = 1;

    while (nr < n - 1) {
        auto next = PQ.top();
        PQ.pop();
        auto nod = next.second.first;
        auto prev = next.second.second;
        if (viz[nod]) {
            continue;
        }
        viz[nod] = 1;
        total-=next.first;
        ++nr;

        muchii.push_back({nod, prev});

        for (auto it:G[nod]) {
            if (!viz[it.first]) {
                PQ.push({-it.second, {it.first, nod}});
            }
        }
    }

    g << total << '\n';
    g << n - 1 << '\n';
    for (auto it:muchii) {
        g << it.first << " " << it.second << '\n';
    }

    return 0;
}