#include <fstream>
#include <vector>
#include <algorithm>
using namespace std;
ifstream be("apm.in");
ofstream ki("apm.out");
const int NMAX=200000;
int findset(int i,vector<int>&parent)
{
if(i==parent[i])
return i;
else findset(parent[i],parent);
}
void unionset(int x,int y,vector<int>&parent)
{
parent[findset(x,parent)]=findset(y,parent);
}
void kruskal(vector<pair<int,pair<int,int> > >&adj,vector<pair<int,int> >&t,vector<int>&parent,int &db,int &m,int &k)
{
int xRep,yRep;
sort(adj.begin(),adj.end());
for(int i=0;i<m;i++)
{
xRep=findset(adj[i].second.first,parent);
yRep=findset(adj[i].second.second,parent);
if(xRep!=yRep)
{
t[k++] = {adj[i].second.first,adj[i].second.second};
db+=adj[i].first;
unionset(xRep,yRep,parent);
}
}
}
int main()
{
int n,m,db=0,k=0;
be>>n>>m;
vector<pair<int,pair<int,int> > >adj;
for(int i=0;i<m;i++)
{
int x,y,c;
be>>x>>y>>c;
adj.push_back({c,{x,y}});
adj.push_back({c,{y,x}});
}
vector<int>parent(n+1);
for(int i=1;i<=n;i++)
parent[i]=i;
vector<pair<int,int> >t(NMAX);
kruskal(adj,t,parent,db,m,k);
ki<<db<<endl;
ki<<k<<endl;
for(int i=0;i<k;i++)
{
ki<<t[i].second<<" "<<t[i].first<<endl;
}
return 0;
}