#include <bits/stdc++.h>

using namespace std;
ifstream f("apm.in");
ofstream g("apm.out");
const int N = 200000;
int n,m,i,T[N],c,cost,x,y,rx,ry,get_root(int);
vector<tuple<int,int,int>> M;
vector<pair<int,int>> sol;
int main()
{
    f>>n>>m;
    for(i=1;i<=n;i++)
        T[i]=i;
    for(;m;m--)
    {
        f>>x>>y>>c;
        M.push_back(make_tuple(c,x,y));
    }
    sort(M.begin(),M.end());
    m=n-1;
    for(auto it:M)
    {
        tie(c,x,y)=it;
        rx=get_root(x);
        ry=get_root(y);
        if(rx!=ry)
        {
            sol.push_back(make_pair(x,y));
            cost+=c;
            T[rx]=ry;
            m--;
        };
        if(!m)break;
    }
    g<<cost<<'\n'<<n-1<<'\n';
    for(auto it:sol)
        g<<it.first<<' '<<it.second<<'\n';
    return 0;
}
int get_root(int nod)
{
    if(nod==T[nod])return nod;
    T[nod]=get_root(T[nod]);
    return T[nod];
}