#include <fstream>
using namespace std;
const char iname[] = "tije.in";
const char oname[] = "tije.out";
ifstream fin(iname);
ofstream fout(oname);
int N;
void read(), write();
void WRT(int x, int y, int num)
{
    for (int i = 1; i <= num; ++i)
    {
        fout << x << ' ' << y << '\n';
    }
}
int main()
{
    read(), write();
    return 0;
}
void read()
{
    fin >> N;
}
void write()
{
    for (int i = 1; i < N; ++i)
    {
        for (int j = N; j >= 1; --j)
            WRT(j, j + 1, i);
        WRT(N + 1, 1, i);
    }
}