How can I limit the max value of number?

Question

I want to secure my page by checking if the value is digital (0,1,2,3) and if it is in the range from 0 to 120. I think ctype_digit function limits numbers, so

Answer 1

if (!ctype_digit($_GET['category']) || $_GET['category'] > 120) die('')

Basically this says "If it's not a number or if it's larger than 120, stop"