#include <fstream>
#include <tuple>
#include <queue>
#include <vector>
using namespace std;
ifstream cin("apm.in");
ofstream cout("apm.out");
int n,m,t[200002],s;
vector<pair<int,int>> g[200002];
priority_queue<tuple<int,int,int>, vector<tuple<int,int,int>>, greater<tuple<int,int,int>>> q;
void Prim(int nod){
    t[nod]=-1;
    int viz=n-1;
    while(viz>0){
        for(auto it : g[nod]){
            if(t[it.first]==0)
                q.push(make_tuple(it.second,it.first,nod));
        }
        while(t[get<1>(q.top())]!=0){
            q.pop();
        }
        s+=get<0>(q.top());
        t[get<1>(q.top())]=get<2>(q.top());
        nod=get<1>(q.top());
        viz--;
    }
}
int main()
{
    cin>>n>>m;
    int a,b,c;
    for(int i=1;i<=m;i++){
        cin>>a>>b>>c;
        g[a].push_back({b,c});
        g[b].push_back({a,c});
    }
    Prim(1);
    t[1]=0;
    cout<<s<<'\n';
    cout<<n-1<<'\n';
    for(int i=2;i<=n;i++){
        cout<<i<<' '<<t[i]<<'\n';
    }
    return 0;
}