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#include <fstream>
#define NMAX 1800
#define INFINIT 999999999
using namespace std;
ifstream fin("apm.in");
ofstream fout("apm.out");
struct vf
{
int ext;
double c;
}g[NMAX][NMAX];
int d[NMAX],n,m,start=1,cmin[NMAX],pre[NMAX],sel[NMAX],cost;
void citire();
void initializare();
void prim();
void afisare();
int main()
{
citire();
initializare();
prim();
afisare();
fin.close();
fout.close();
return 0;
}
void citire()
{
int x,y,c,i;
fin>>n>>m;
for(i=1;i<=m;i++)
{
fin>>x>>y>>c;
++d[x]; ++d[y];
g[x][d[x]].ext=y;
g[x][d[x]].c=c;
g[y][d[y]].ext=x;
g[y][d[y]].c=c;
}
}
void initializare()
{
int i;
for(i=1;i<=n;i++)
{
cmin[i]=INFINIT;
pre[i]=start;
}
cmin[start]=pre[start]=0;
for(i=1;i<=d[start];i++)
cmin[g[start][i].ext]=g[start][i].c;
sel[start]=1;
}
void prim()
{
int nr=n-1,vfmin,i,minim;
while(nr>0)
{
minim=INFINIT;
for(i=1;i<=n;i++)
{
if(cmin[i]<minim && !sel[i])
{
minim=cmin[i];
vfmin=i;
}
}
sel[vfmin]=1;
--nr;
for(i=1;i<=d[vfmin];i++)
{
if(g[vfmin][i].c<cmin[g[vfmin][i].ext] && !sel[g[vfmin][i].ext])
{
cmin[g[vfmin][i].ext]=g[vfmin][i].c;
pre[g[vfmin][i].ext]=vfmin;
}
}
}
}
void afisare ()
{
int i;
for (i=1;i<=n;i++)
cost+=cmin[i];
fout<<cost<<'\n'<<n-1<<'\n';
for(i=1;i<=n;i++)
{
if(i!=start)
fout<<pre[i]<<' '<<i<<'\n';
}
}