#include <iostream>
#include <fstream>
using namespace std;


ifstream fin("tije.in");
ofstream fout("tije.out");
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;
	fin.close();
}

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);
	}
	fout.close();
}