#include <fstream>
#include <vector>
#include <queue>

using namespace std;
ifstream cin("apm.in");
ofstream cout("apm.out");
int d[200005],pred[200005];
vector<pair<int,int>> v[200005],ans;
priority_queue<pair<int,int>> q;
bool inq[200005];
int main()
{
    int n,m,cost=0;
    cin>>n>>m;
    for(int i=2;i<=n;i++)
        d[i]=1<<30;
    for(int i=1;i<=m;i++)
    {
        int x,y,c;
        cin>>x>>y>>c;
        v[x].push_back({y,c});
        v[y].push_back({x,c});
    }
    q.push({0,1});
    while(!q.empty())
    {
        int x=q.top().second;
        //cout<<x<<" ";
        q.pop();
        if(inq[x])
           continue;
        cost+=d[x];
        if(pred[x])
           ans.push_back({pred[x],x});
        inq[x]=true;
        for(auto i:v[x])
        {
            int y=i.first,c=i.second;
            //cout<<x<<" "<<y<<"\n";
            if(!inq[y] && d[y]>c)
               d[y]=c,pred[y]=x,q.push({-c,y});
        }
    }
    cout<<cost<<"\n"<<ans.size()<<"\n";
    for(auto i:ans)
        cout<<i.first<<" "<<i.second<<"\n";
    return 0;
}