#include <iostream>
using namespace std;

int main()
{
    int input;
    int result;
    int tmp[4] = {2,3,2,4};
    while(cin>>input)
    {
        if(input == 1||input == 2)
        {
            result = -1;
        }
        else
        {
            result = tmp[(input -3)%4];
        }
        cout << result <<endl;
    }
    return 0;
}