#include <fstream>

using namespace std;

int main()
{
    int n;
    ifstream f("lacate.in");
    f >> n;
    f.close();
    ofstream g("lacate.out");
    if(n == 2)
        g << "1 1\n1\n1\n";
    else
    {
        g << n << " 2\n";
        for(int i = 1; i < n; i++)
            g << i << " " << i + 1 << '\n';
        g << n << " " << 1 << '\n';
    }
    g.close();
    return 0;
}