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#include <bits/stdc++.h>
using namespace std;
ifstream fin("apm.in");
ofstream fout("apm.out");
const int dim=420000;
long long cost=0;
int ans=0;
int rang[200001];
struct muchie{
int x,y,c;
}g[dim];
struct pair{
int prim;
int secund;
}rez[dim];
int n,m;
int t[200005];
bool compara(muchie a,muchie b){
if (a.c<b.c) return 1;
return 0;
}
void citire()
{
fin>>n>>m;
for (int i=1;i<=m;i++)
{
fin>>g[i].x>>g[i].y>>g[i].c;
}
}
int radacina(int x)
{
while(t[x]!=x)
{
x=t[x];
}
return x
;
}
void uneste(int a,int b)
{
if (rang[a]<rang[b]) t[a]=b;
else if (rang[b]<rang[a]) t[b]=a;
else if (rang[b]==rang[a])
{
rang[a]++;
t[a]=b;
}
}
void kruskal()
{
sort(g+1,g+1+m,compara);
for (int i=1;i<=n;i++) {
t[i]=i;
}
for (int i=1;i<=m && ans<n;i++)
{
int a=radacina(g[i].x);
int b=radacina(g[i].y);
if (a!=b)
{
uneste(a,b);
cost+=g[i].c;
rez[++ans].prim=g[i].x;
rez[ans].secund=g[i].y;
}
}
fout<<cost<<'\n'<<n-1<<'\n';
for (int i=1;i<n;i++)
{
fout<<rez[i].prim<<' '<<rez[i].secund<<'\n';
}
}
int main()
{
citire();
kruskal();
}