w02d03_morning_exercise_solution_prime_numbers

w02d03_morning_exercise_solution.js

////////////////////////////////////////////////
//Part One
///////////////////////////////////////////////
var isPrime = function(num) {
	// Prime is any number greater than 1.
    if (num < 2) { return false };

	//First section, see if the number entered is evenly divisible by any number (other than 1).
	//Second section, as per the instructions, you only need to test up to the square root of the number.
	//third is just increasing the number that is checked each time.
    for (var i=2; i <= Math.sqrt(num); i++) {
        if (num % i === 0) {
            return false;
        }
    }
    return true;
}

console.log(isPrime(11));

///////////////////////////////////////////////
//Part Two
///////////////////////////////////////////////
var printPrimes = function(limit) {
	//first section represents the number that will go through the `isPrime` function.
	//second section sets the limit - check for prime numbers only up to this number.
	//third is just increasing the number that is checked each time.
    for (var i=1; i <= limit; i++) {
        if (isPrime(i)) {
        	//if the number is a prime, the `isPrime` function returns `true` and this triggers the console.log.
            console.log(i);
        }
    }
}

console.log(printPrimes(97));