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#include <stdio.h>
#include <vector>
#include <algorithm>
using namespace std;
int n,m,i,cost,t[200001],h[200001],a,b;
vector<pair<int,int> > r;
struct edge
{
int x,y,c;
}e[400001];
bool cmp(edge a,edge b)
{
return a.c<=b.c;
}
int arb(int n)
{
while (t[n]) n=t[n];
return n;
}
void kruskal()
{
int i,j=0;
for (i=1;i<n;i++)
{
while (true)
{
j++;
a=arb(e[j].x);
b=arb(e[j].y);
if (a!=b) break;
}
r.push_back(make_pair(e[j].x,e[j].y));
cost+=e[j].c;
if (h[a]>h[b]) t[b]=a;
else if (h[a]<h[b]) t[a]=b;
else
{
h[a]++;
t[b]=a;
}
}
}
int main()
{
freopen ("apm.in","r",stdin);
freopen ("apm.out","w",stdout);
scanf("%i%i",&n,&m);
for (i=1;i<=m;i++)
scanf("%i%i%i",&e[i].x,&e[i].y,&e[i].c);
sort(e+1,e+m+1,cmp);
kruskal();
printf("%i\n%i\n",cost,n-1);
for (i=0;i<r.size();i++)
printf("%i %i\n",r[i].first,r[i].second);
fclose(stdin);
fclose(stdout);
return 0;
}