Can there exist two functions f and g that take only integer values such that for any integer x the following relations hold:
a) f(f(x))=x, g(g(x))=x, f(g(x))>x, g(f(x))>x?
b) f(f(x))<x, g(g(x))<x, f(g(x))>x, g(f(x))>x?