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.
int sum =0;
for(int i=1;i<1000;i++){
if(i%3 == 0 || i%5 == 0)
sum += i;
}
Console.WriteLine(sum);