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#include <cstdio>
#include <utility>
#include <algorithm>
using namespace std;
pair <int, pair <int, int> > a[400004];
vector <pair <int, int> > v;
int i,n,m,p[200004],r[200004],x,y,s;
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;
while (p[x]!=x)
x=p[x];
while (p[y]!=y)
y=p[y];
if (x!=y)
{
s+=a[i].first;
v.push_back(pair<int,int> (x, y));
if (r[x]>r[y])
p[y]=x;
else if (r[x]<r[y])
p[x]=y;
else
{
p[y]=x;
r[x]++;
}
}
}
printf ("%d\n", s);
printf ("%d\n", v.size());
for (i=0;i<=(v.size()-1);i++)
printf ("%d %d\n", v[i].first, v[i].second);
return 0;
}