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#include <cstdio>
#include <algorithm>
#include <utility>
using namespace std;
pair <int, pair <int, int> > a[400004];
pair <int, int> v[400004];
int i,n,m,p[200004],r[200004],x,y,s,x1,y2,nr;
int main()
{
freopen ("apm.in","r",stdin);
freopen ("apm.out","w",stdout);
scanf ("%d %d", &n, &m);
for (i=1;i<=m;i++)
scanf ("%d %d %d", &a[i].second.first, &a[i].second.second, &a[i].first);
sort (a+1,a+m+1);
for (i=1;i<=n;i++)
{
p[i]=i;
r[i]=1;
}
for (i=1;i<=m;i++)
{
x=a[i].second.first;
y=a[i].second.second;
x1=x;
y2=y;
while (p[x1]!=x1)
x1=p[x1];
while (p[y2]!=y2)
y2=p[y2];
if (x1!=y2)
{
s+=a[i].first;
v[++nr].first=x;
v[nr].second=y;
if (r[x1]>r[y2])
p[y2]=x1;
else if (r[x1]<r[y2])
p[x1]=y2;
else
{
p[y2]=x;
r[x1]++;
}
}
}
printf ("%d\n", s);
printf ("%d\n", nr);
for (i=1;i<=nr;i++)
printf ("%d %d\n", v[i].first, v[i].second);
return 0;
}