#include <bits/stdc++.h>

using namespace std;
ifstream f("apm.in");
ofstream g("apm.out");
const int N = 200010;
int n,m,Cst,c,x,y,k,T[N],rx,ry,get_root(int);
vector<tuple<int,int,int>> E;
vector<pair<int,int>>sol;
int main()
{
    f>>n>>m;
    k=n;
    for(int i=1;i<=n;i++)
        T[i]=i;
    for(;m;m--)
    {
        f>>x>>y>>c;
        E.push_back(make_tuple(c,x,y));
    }
    sort(E.begin(),E.end());
    for(auto it:E)
    {
        tie(c,x,y)=it;
        rx=get_root(x);
        ry=get_root(y);
        if(rx!=ry)
        {
            T[rx]=ry;
            Cst+=c;
            sol.push_back(make_pair(x,y));
        }
    }
    g<<Cst<<'\n';
    g<<n-1<<'\n';
    for(auto it:sol)
        g<<it.first<<' '<<it.second<<'\n';
    return 0;
}
int get_root(int nod)
{
    if(T[nod]==nod)
        return nod;
    T[nod]=get_root(T[nod]);
    return T[nod];
}