#include <bits/stdc++.h>

using namespace std;

ifstream fin("apm.in");
ofstream fout("apm.out");

int i,j,n,p,dist[200005],a,b,val,viz[200005],nod,vecin,m,tata[200005],sum;
priority_queue<int,vector<int>,greater<int>> pq;
vector <pair<int,int>> v[200005];

int main()
{
fin>>n>>m;
for(i=1;i<=n;i++){
    dist[i] = 1000000000;
}
for(i=1;i<=m;i++){
    fin>>a>>b>>val;
    v[a].push_back({b,val});
    v[b].push_back({a,val});
}
p = 1;
pq.push(p);
dist[p] = 0;
while(!pq.empty()){
    nod = pq.top();
    pq.pop();
    //vecin
    if(!viz[nod]){
    for(i=0;i<v[nod].size();i++){
        vecin = v[nod][i].first;
        val = v[nod][i].second;
        if(val < dist[vecin] && tata[nod] != vecin){
            dist[vecin] = val;
            pq.push(vecin);
            tata[vecin] = nod;
        }
    }
    viz[nod] = 1;
    }
}
for(i=2;i<=n;i++){
    sum += dist[i];
}
fout << sum << '\n';
fout << n - 1 << '\n';
for(i=1;i<=n;i++){
    fout << i << " " << tata[i] << '\n';
}
    return 0;
}