Description

Determine if a number is a prime.

A prime number is a numeral that is greater than 1 and cannot be divided evenly by any other number except 1 and itself. If a number can be divided evenly by any other number not counting itself and 1, it is not prime and is referred to as a composite number.

Example 1:

Input:  7
Output: true

Example 2:

Input:  4
Output: false