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#include <bits/stdc++.h>
#define M 400001
#define N 200001
using namespace std;
ifstream fin ("apm.in");
ofstream fout ("apm.out");
int n,m,x,y,z,cost,nr;
int t[N],h[N];
struct lista
{
int x,y,c,sel;
};
lista l[M];
bool cmp(lista A ,lista B)
{
return A.c<B.c;
}
void Citire()
{
fin>>n>>m;
for(int i=1;i<=m;++i)
{
fin>>x>>y>>z;
l[i].x=x;l[i].y=y;l[i].c=z;l[i].sel=0;
}
}
int root(int x)
{
while(t[x]!=x)
x=t[x];
return x;
}
void Uniune(int x,int y)
{
if(h[x]>h[y])
t[y]=x;
else if(h[y]>h[x])
t[x]=y;
else
{
h[x]++;
t[y]=x;
}
}
void Kruskal()
{
for(int i=1;i<=n;++i)
{
t[i]=i;
h[i]=1;
}
sort(l+1,l+m+1,cmp);
cost=0;nr=0;
for(int i=1;i<=m&&nr<n-1;i++)
{
int r1=root(l[i].x);
int r2=root(l[i].y);
if(r1!=r2)
{
Uniune(r1,r2);
nr++;
cost+=l[i].c;
l[i].sel=1;
}
}
fout<<cost<<'\n';
fout<<n-1<<'\n';
for(int i=1;i<=m;++i)
if(l[i].sel==1)
fout<<l[i].x<<" "<<l[i].y<<'\n';
}
int main()
{
Citire();
Kruskal();
return 0;
}