Student here. I'm missing a single rubric item in the following project program and can't figure out where to place it, "it" being a pass-by-reference item. If anyone is feeling generous, please take a look at my program below and give me a heads-up about where I could tweak the code to make pass-by-reference possible. As it stands, I'm stumped and I don't have enough time to come up with an entirely new problem for which to code a solution. Thank you all in advance!

```
#include <iostream>
#include <cmath>
using namespace std;

//Global Variable
int height = 0;

//Function Prototypes
int getMale();
int getFemale();

int main()
{

    //Local Variable
    int ideal = 0;
    char sex(' ');

    //Sequence Structure
    cout << "Welcome to the Hamwi Ideal Body Weight Equation Calculator!" << endl;
    cout << "Please enter your height in inches (remember, 1 foot = 12 inches): " << endl;
    cin >> height;

    cout << "Please enter your biological sex (M or F): " << endl;
    cin >> sex;

    //Repetition Structure
    while (toupper(sex) != 'M' && 'F')
    {
        cout << "Invalid entry. Please enter your biological sex (M or F): " << endl;
        cin >> sex;
    } //end while

    //Selection Structure
    if (toupper(sex) == 'M')
    {
        int ideal = getMale();
        cout << "Thank you. Your ideal body weight is approximately: " << ideal << " pounds." << endl;
        cout << "Have a nice day!" << endl;
    } //end if

    else
    {
        int ideal = getFemale();
        cout << "Thank you. Your ideal body weight is approximately: " << ideal << " pounds." << endl;
        cout << "Have a nice day!" << endl;
    } //end else

    return 0;
} //end of main function

//Program-Defined Function #1 (Male)
int getMale()
{
    //Local Variable
    int male = 0;

    if (height >= 60)
    {
        male = 106 + ((height - 60) * 6);
        return male;
    } //end if

    else
    {
        male = 106 - ((60 - height) * 6);
        return male;
    } //end else
} //end of male function

//Program-Defined Function #2 (Female)
int getFemale()
{
    //Local Variable
    int female = 0;

    if (height >= 60)
    {
        female = 100 + ((height - 60) * 5);
        return female;
    } //end if

    else
    {
        female = 100 - ((60 - height) * 5);
        return female;
    } //end else
} //end of female function

```