# Simple Programming Question

I'm teaching myself C++ and am stuck on this VERY simple problem. I'm not sure what's wrong with my code.

The problem is from https://projecteuler.net/ if anyone is wondering.

## Homework Statement

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.

## The Attempt at a Solution

Code:
#include <iostream>
using namespace std;

int main()
{

num = 1;
while(num < 1001)
{
if(num % 3 == 0 || num % 5 == 0)
{
}
num = num + 1;
}
return 0;
}

The answer I get from this is 234168 but the site says this is wrong.