Find the sum of all the multiples of 3 or 5 below 1000

Question

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. I have the following code but the answer do

Answer 1

Two things:

• you're including 1000 in the loop, and
• you're adding one to the sum each time, rather than the value itself.

Change the loop to

for(i=0;i<1000;i++)

And the sum line to

sum=sum+i;