How do I scale down numbers from rand()?

Question

The following code outputs a random number each second:

int main ()
{
    srand(time(NULL)); // Seeds number generator with execution time.

    while (true)         


        

Answer 1

Some people have posted the following code as an example:

int rawRand = (rand() / RAND_MAX) * 100;

This is an invalid way of solving the problem, as both rand() and RAND_MAX are integers. In C++, this results in integral division, which will truncate the results decimal points. As RAND_MAX >= rand(), the result of that operation is either 1 or 0, meaning rawRand can be only 0 or 100. A correct way of doing this would be the following:

int rawRand = (rand() / static_cast(RAND_MAX)) * 100;

Since one the operands is now a double, floating point division is used, which would return a proper value between 0 and 1.