Euler1.js

/*

If we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3, 5, 6 and 9. The sum of these multiples is 23.

Find the sum of all the multiples of 3 or 5 below 1000.

*/

function sum_of_mul(num){
	var sum = 0;
	for(var i=0;i <num; i++){
		if (i % 3 == 0 || i % 5 == 0){
			sum += i;
		}
	}
	return sum;

}

console.log("sum of multiples of 3 and 5 below 1000", sum_of_mul(1000) );