1 - multiples of 3 and 5

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.

link

cevap : 233168

clear all;
clc;
close all;

sum = 0; 
for i=1:999
    if (mod(i,3) == 0)
        sum = sum + i;
    end
    if(mod(i,5) == 0)
        sum = sum + i;
    end
    if(mod(i,15) == 0)
        sum = sum - i;
    end
end