#include<fstream>
#include<vector>
#include<algorithm>
#include<queue>
using namespace std;
ifstream in("apm.in");
ofstream out("apm.out");
struct muchie{
    int vf;
    int cost;
};
muchie makeMuchie(int a , int b)
{
    muchie x;
    x.vf=a;
    x.cost=b;
    return x;
}
const int N = 200001;
const int INF= 1001;
vector <muchie> a[N];
priority_queue < pair<int,int> > minHeap;
int d[N],marcat[N],pred[N],cost,n,m,x,y,c;
int main()
{
    in>>n>>m;
    for(int i=1;i<=m;i++)
    {
        in>>x>>y>>c;
        a[x].push_back(makeMuchie(y,c));
        a[y].push_back(makeMuchie(x,c));
    }
    for(int i=2;i<=n;i++)
        d[i]=INF;
    minHeap.push(make_pair(0,1));
    for(int i=2;i<=n;i++)
    {
        while(marcat[minHeap.top().second])
            minHeap.pop();
        cost+=minHeap.top().first;
        int x=minHeap.top().second;
        marcat[x]=1;
        minHeap.pop();

        for(int i=0;i<a[x].size();i++)
        {
            int dist=a[x][i].cost;
            if(dist<d[a[x][i].vf])
            {
                d[a[x][i].vf]=dist;
                pred[a[x][i].vf]=x;
                minHeap.push(make_pair(-dist,a[x][i].vf));
            }
        }
    }
    while(marcat[minHeap.top().second])
            minHeap.pop();
        cost+=minHeap.top().first;
    out<<-cost<<"\n"<<n-1<<"\n";
    for(int i=2;i<=n;i++)
        out<<i<<" "<<pred[i]<<"\n";
    return 0;
}