This one should be easy.
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.
A simple loop and a remainder check.
public class Euler1
{
public static void main(String[] args)
{
Euler1 e = new Euler1();
System.out.print(“Problem 1:\nSum = ” + e.Problem1()+ “\n”);
}public String Problem1 ()
{
int sum = 0;
for (int i = 1; i < 1000; i++)
{
if (i%3 == 0 || i%5 == 0)
{
sum += i;
}
}
return String.valueOf(sum);
}
}