#include <cstdio>
#include <vector>
#include <queue>
#include <bitset>

using namespace std;

const int maxN = 200005;
const int inf = 100000;

int n, m;
vector<pair<int, int> > vecini[maxN];
int cost[maxN];
int tata[maxN];
bitset<maxN> viz;

void citire()
{
    scanf("%d %d", &n, &m);

    int tmp1, tmp2, tmp3;

    for(int i = 0; i < m; i++)
    {
        scanf("%d %d %d", &tmp1, &tmp2, &tmp3);

        vecini[tmp1].push_back(make_pair(tmp3, tmp2));
        vecini[tmp2].push_back(make_pair(tmp3, tmp1));
    }

    for(int i = 0; i < maxN; i++)
    {
        cost[i] = inf;
    }
}

void prim()
{
    priority_queue<pair<int, int>, vector<pair<int, int> >, greater<pair<int, int> > > Q;

    Q.push(make_pair(0, 1));
    int costTotal = 0;
    vector<pair<int, int> > solutie;
    cost[1] = 0;
    tata[1] = 1;

    while(!Q.empty())
    {
        int _cost, _nod;

        _cost = Q.top().first;
        _nod = Q.top().second;

        Q.pop();
        viz[_nod] = true;

        int l = vecini[_nod].size();

        for(int i = 0; i < l; i++)
        {
            if(viz[vecini[_nod][i].second] == false && cost[vecini[_nod][i].second] > vecini[_nod][i].first)
            {
                Q.push(vecini[_nod][i]);
                cost[vecini[_nod][i].second] = vecini[_nod][i].first;
                tata[vecini[_nod][i].second] = _nod;
            }
        }
    }

    for(int i = 1; i <= n; i++)
    {
        costTotal += cost[i];
    }

    printf("%d\n%d\n", n - 1, costTotal);

    for(int i = 2; i <= n; i++)
    {
        printf("%d %d\n", i, tata[i]);
    }
}

int main()
{
    freopen("apm.in", "r", stdin);
    freopen("apm.out", "w", stdout);

    citire();
    prim();

    return 0;
}