I'm trying to make an app on Xcode (Swift) that checks whether a number is prime or not.
Can someone help me with some pseudocode to check the number?
I need a simple answer, not incredibly advanced algorithms. I'm new to programming.
A simple method is to check all factors up to the square-root of the number. This is NOT the most efficient method, but is sufficient for most numbers you will likely be inputting in an iPhone app. (see https://en.wikipedia.org/wiki/Primality_test for more complex algorithms).
function is_prime(n: int) if n <= 1 return false if n <= 3 return true i = 2 while i*i <= n if n % i == 0 return false i = i + 1 return true