#include<fstream.h>
ifstream f("lacate.in");
ofstream g("lacate.out");
int n,i;
int main()
{
f>>n;
if(n==1)
g<<1<<" "<<1<<'\n'<<1<<'\n';
else
if(n==2)
g<<1<<" "<<1<<'\n'<<1<<'\n';
else
{
g<<n<<" "<<2<<'\n';
for(i=1;i<n;i++)
g<<i<<" "<<i+1<<'\n';
g<<n<<" "<<1<<'\n';
}
f.close();
g.close();
return 0;
}