Math Number Theory
Learner Level

Implement the isPrimeNumber method that checks whether the given number is prime.

The input contains an integer n. Your task is to check whether n is a prime number.

A prime number is greater than 1 and has exactly two factors: 1 and itself. For example, 7 is prime, but 10 is not because it is divisible by 2 and 5.

Example 1
Input:
n (int) = 7
Return:
(boolean) true
Example 2
Input:
n (int) = 10
Return:
(boolean) false
Example 3
Input:
n (int) = 1
Return:
(boolean) false

First reject numbers less than or equal to 1, because they are not prime.

For larger numbers, test possible divisors from 2 up to the square root of n. If any divisor divides n exactly, the number is not prime. If no divisor is found, the number is prime.

Pseudocode:

function isPrimeNumber(n):
    if n <= 1:
        return false
    divisor = 2
    while divisor * divisor <= n:
        if n % divisor == 0:
            return false
        divisor++
    return true
Run your code to see the result.