Compute Median of Values Stored In Vector - C++?

Question

I\'m a programming student, and for a project I\'m working on, on of the things I have to do is compute the median value of a vector of int values. I\'m to do this using onl

Answer 1

const int DIVISOR = 2;

Don't do this. It just makes your code more convoluted. You've probably read guidelines about not using magic numbers, but evenness vs. oddness of numbers is a fundamental property, so abstracting this out provides no benefit but hampers readability.

if ((hWScores.size() % DIVISOR) == 0)
{
    median = ((hWScores.begin() + hWScores.size()) + (hWScores.begin() + (hWScores.size() + 1))) / DIVISOR);

You're taking an iterator to the end of the vector, taking another iterator that points one past the end of the vector, adding the iterators together (which isn't an operation that makes sense), and then dividing the resulting iterator (which also doesn't make sense). This is the more complicated case; I'll explain what to do for the odd-sized vector first and leave the even-sized case as an exercise for you.

}
else 
{
    median = ((hWScores.begin() + hWScores.size()) / DIVISOR)

Again, you're dividing an iterator. What you instead want to do is to increment an iterator to the beginning of the vector by hWScores.size() / 2 elements:

    median = *(hWScores.begin() + hWScores.size() / 2);

And note that you have to dereference iterators to get values out of them. It'd be more straightforward if you used indices:

    median = hWScores[hWScores.size() / 2];