/*
TASK:mate
LANG:C++
*/

#include <iostream>

using namespace std;

int main()
{
	int n;
	cin>>n;
	cout<<'5'<<endl<<"2-4 5-1 3-2 4-5"<<endl<<"1-3 4-2 3-5"<<endl<<"3-1 1-5 2-3 5-4"
		<<endl<<"1-2 2-5 3-4 5-3 4-1"<<endl<<"5-2 4-3 1-4 2-1"<<endl;
	return 0;
}