Program for Sum of Multiples

SumOfMultiples

public class SumOfMultiples {

	public static int sumOfMultiples(int first, int second, int high){
		//use summation
		
		int ceiling = high-1;
		//need to subtract the overlapping elements
		int product = first * second;
		
		//find the biggest multiple less than 1000
		int first_multiple = ceiling / first;
		int second_multiple = ceiling / second;
		int product_multiple = ceiling / product;
		
		//summation of each
		int f_sum = first * (first_multiple * (first_multiple+1))/2;
		int s_sum = second * (second_multiple * (second_multiple+1))/2;
		int p_sum = product * (product_multiple * (product_multiple+1))/2;

		//subtract overlapping elements
		return f_sum + s_sum - p_sum;
	}
	
	public static void main(String[] args){
		int solution = sumOfMultiples(3,5,1000);
		System.out.println(solution);
	}
	
}