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#include <fstream>
#include<algorithm>
#include <vector>
#define INF 100000000
using namespace std;
ifstream fin ("apm.in");
ofstream fout("apm.out");
struct muc {int vec,cost;}mu1,mu2;
vector <muc> G[400005];
int prec[200005],cmin[200005];
bool uz[200005];
void citire();
void rez();
bool comp (muc a,muc b);
int n,m;
int main()
{
citire();
rez();
return 0;
}
void citire()
{
int x,y,co;
fin>>n>>m;
for(int i=1; i<=m; i++)
{
fin>>x>>y>>co;
mu1.cost=co;
mu1.vec=y;
mu2.cost=co;
mu2.vec=x;
G[x].push_back(mu1);
G[y].push_back(mu2);
}
}
void rez ()
{
int i,cn,costtot,mini,nod;
for(i=2;i<=n;i++)
{
prec[i]=1;
cmin[i]=INF;
}
uz[1]=1;
for(i=0; i<G[1].size(); i++)
if(cmin[G[1][i].vec] > G[1][i].cost)
{
cmin[G[1][i].vec]=G[1][i].cost;
prec[G[1][i].vec]=1;
}
cn=n-1;
costtot=0;
while(cn)
{
cn--;
mini=INF;
for(i=1;i<=n;i++)
if(!uz[i])
if(cmin[i]<mini)
{
mini=cmin[i];
nod=i;
}
uz[nod]=1;
costtot+=mini;
for(i=0; i<G[nod].size(); i++)
if(cmin[G[nod][i].vec] > G[nod][i].cost)
{
cmin[G[nod][i].vec]=G[nod][i].cost;
prec[G[nod][i].vec]=nod;
}
}
fout<<costtot<<'\n';
fout<<n-1<<'\n';
for(i=2;i<=n;i++)
fout<<i<<" "<<prec[i]<<'\n';
}