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#include<fstream>
#include<set>
#include<vector>
#define INF 1<<30
using namespace std;
int m,n,tata[200001],dist[200001],s,viz[200001];
vector<pair<int,int> > v[200001];
set<pair<int,int> > cost;
ifstream fin("apm.in");
ofstream fout("apm.out");
void Citire()
{
int x,y,c;
fin>>n>>m;
for(int i=1;i<=m;i++)
{
fin>>x>>y>>c;
v[x].push_back(make_pair(y,c));
v[y].push_back(make_pair(x,c));
}
}
void Initializare()
{
for(int i=2;i<=n;i++)
{
dist[i]=INF;
}
for(int i=0;i<v[1].size();i++)
{
cost.insert(make_pair(v[1][i].second,v[1][i].first));
tata[v[1][i].first]=1;
dist[v[1][i].first]=v[1][i].second;
}
viz[1]=1;
}
void Prim()
{
int nod;
for(int i=1;i<n;i++)
{
nod=(*cost.begin()).second;
while(viz[nod]==1)
{
cost.erase(*cost.begin());
nod=(*cost.begin()).second;
}
viz[nod]=1;
s+=dist[nod];
cost.erase(*cost.begin());
for(int j=0;j<v[nod].size();j++)
{
if(dist[v[nod][j].first]>v[nod][j].second && viz[v[nod][j].first]==0)
{
dist[v[nod][j].first]=v[nod][j].second;
cost.insert(make_pair(v[nod][j].second,v[nod][j].first));
tata[v[nod][j].first]=nod;
}
}
}
}
void Afisare()
{
fout<<s<<"\n"<<n-1<<"\n";
for(int i=2;i<=n;i++)
fout<<i<<" "<<tata[i]<<"\n";
}
int main()
{
Citire();
Initializare();
Prim();
Afisare();
return 0;
}