#include<stdio.h>
#include<algorithm>
#include<vector>
#define pb push_back

using namespace std;

const int maxn = 400100;

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

int root(int i)
{
    while (i!=GR[i]) i=GR[i];
    return i;
}

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

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

int main()
{
    freopen("amp.in","r",stdin);
    freopen("amp.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;
    sort(IND + 1,IND + M + 1,cmpf);
    for(int i = 1;i <= M; ++i)
    {
        if (root(X[IND[i]]) != root(Y[IND[i]])){
            cost_total += C[IND[i]];
            reuniune(X[IND[i]],Y[IND[i]]);
            VANS.pb(IND[i]);
        }
    }
    printf("%d\n",cost_total);
    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;
}