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#include <iostream>
#include <queue>
#include <fstream>
#include <vector>
#define Nmax 100000
using namespace std;
ifstream fin("apm.in");
ofstream fout("apm.out");
vector<pair<int,int>> g[Nmax];
int TT[Nmax];
int d[Nmax];
bool viz[Nmax];
int sum,n,m,x,y,c;
void prim(int start)
{
priority_queue<pair<int,int>,vector<pair<int,int>>,greater<pair<int,int>>> pq;
pq.push(make_pair(0,start));
while(!pq.empty())
{
int nod=pq.top().second;
pq.pop();
if(!viz[nod])
{
for(auto i : g[nod])
{
if(d[i.second]>i.first && !viz[i.second])
{
d[i.second]=i.first;
TT[i.second]=nod;
pq.push(make_pair(i.first,i.second));
}
}
}
viz[nod]=true;
}
}
int main()
{
fin>>n>>m;
for(int i=1;i<=m;i++)
{
fin>>x>>y>>c;
g[x].push_back(make_pair(c,y));
g[y].push_back(make_pair(c,x));
}
for(int i=2;i<=n;i++)
d[i]=INT_MAX;
prim(1);
for(int i=2;i<=n;i++)
sum+=d[i];
fout<<sum<<'\n';
fout<<n-1<<'\n';
for(int i=2;i<=n;i++)
fout<<i<< " " <<TT[i]<< '\n';
return 0;
}