#include <stdio.h>
#include <algorithm>
#include <vector>

using namespace std;

const int maxn = 400100;

int GR[maxn], X[maxn], Y[maxn], C[maxn];
int N, M, ANS, IND[maxn];
vector<int> VANS;

int grupa(int i)
{
    if (GR[i] == i)
        return i;
    GR[i] = grupa(GR[i]);
    return GR[i];
}

void reuniune(int i, int j)
{
    GR[grupa(i)] = grupa(j);
}

bool cmpf(int i, int j)
{
    return (C[i] < C[j]);
}

int main()
{
    freopen("apm.in", "r", stdin);
    freopen("apm.out", "w", stdout);
    scanf("%d %d\n", &N, &M);
    for (int i = 1; i <= M; ++i)
    {
        scanf("%d %d %d\n", &X[i], &Y[i], &C[i]);
        IND[i] = i;
    }

    for (int i = 1; i <= N; ++i)
        GR[i] = i;
    for (int i = 1; i <= N; ++i)
        GR[i] = i;
    sort(IND + 1, IND + M + 1, cmpf);
    for (int i = 1; i <= M; ++i)
    {
        if (grupa(X[IND[i]]) != grupa(Y[IND[i]]))
        {
            ANS += C[IND[i]];
            reuniune(X[IND[i]], Y[IND[i]]);
            VANS.push_back(IND[i]);
        }
    }
    printf("%d\n", ANS);
    printf("%d\n", N - 1);
    for (int i = 0; i < N - 1; ++i)
        printf("%d %d\n", X[VANS[i]], Y[VANS[i]]);
    return 0;
}