public static boolean isPrime(int num) { // isPrime returns a boolean and takes an int as an argument; it checks if it's argument is prime
		double numSqrt = Math.sqrt(num); // Get the square root of num. We only have to check values less than or equal to sqrt(x) to see if x is prime
		boolean prime = true; // prime returns whether or not num is prime

		if (num != 1) { // If num isn't 1:
			for (int i = 2; i <= numSqrt; i ++) { // For each number i, starting from 2, less than or equal to sqrt(num):
				if (num % i == 0) { // If num is evenly divisible by i:
					prime = false; // num is not a prime, so we set prime to false
					break; // Leave the loop
				}
			}
		}
		
		else { // If num is 1:
			prime = false; // num isn't a prime, so we set prime to false
		}
		
		return prime; // Return prime
	}