Task

The objective is to write a function that finds the sum of all positive multiples of 3 or 5 below n.

Show output for n = 1000.

This is is the same as Project Euler problem 1.

Extra credit: do this efficiently for n = 1e20 or higher.




class SumMultiples {
	public static long getSum(long n) {
		long sum = 0;
		for (int i = 3; i < n; i++) {
			if (i % 3 == 0 || i % 5 == 0) sum += i;
		}
		return sum;
	}
	public static void main(String[] args) {
		System.out.println(getSum(1000));
	}
}