#include <iostream>
using namespace std;

const int MAX_SIZE = 100;
int ArraySize = 0;

//Function Prototypes.
void GetUserInput(double []);
void SortArray(double []);
void ShowMedian(double []);

int main()
{
    //This is the exit condition.
    bool exit = false;
    double numbers[MAX_SIZE];

    char action;

    GetUserInput(numbers);
    do
    {
    cout << "\nPlease select action\n"
    //These are the menu choices.
    "1) Show the median\n"
    "2) Input new numbers\n"
    "3) Exit the program! ";

    cin.get(action);
    getchar();

    if(action == '1')
    ShowMedian(numbers);
    else if(action == '2')
    GetUserInput(numbers);
    else if(action == '3')
    exit = true;
    else
    cout << "\n\nInvalid action\n\n";

    }while(!exit);

    //Pause the system to display the results.
    system("\nPause");

}

//The GetUserInput function will get the user's input from the keyboard.
void GetUserInput(double numbers[MAX_SIZE])
{
    //The exit the program condition.
    bool exit = false;

    //Clear the array so that new numbers can be entered.
    for(int i=0; i < MAX_SIZE; i++)
    numbers[i] = 0;


    //Using a do-while loop to ask the user to enter the number of numbers
    //that she wishes to enter.
    do
    {
    cout << "\nHow many numbers are you going to enter? > ";
    cin >> ArraySize;

    //Capture the enter key.
    getchar();

    if(ArraySize > MAX_SIZE || ArraySize == 0)
    cout << "\nInvalid number\n";

    }while(ArraySize == 0 || ArraySize > MAX_SIZE);

    //Ask the user to enter positive numbers.
    for(int i = 0; i < ArraySize; i++)
    {
        cout << "\nPlease enter a positive number: ";
        cin >> numbers[i];
        getchar();
    }

}

//The ShowMedian function will take an array of numbers, and an integer
//indicating the size of the array and then return the median of the values
//in the array.
void ShowMedian(double numbers[MAX_SIZE])
{
    SortArray(numbers);

    int medIndex = 0;
    double median = 0;

    //If median is 1/2 way between.
    if((ArraySize % 2) != 0)
    {
    medIndex = ((ArraySize-1) / 2);
    median = numbers[medIndex];
    }
    else
    {
    medIndex = ArraySize / 2;
    median = ((numbers[medIndex] + numbers[medIndex +1 ])/2);
    }

    cout << "\nThe median is: " << median << endl;
}

//The SortArray function will sort the array in order.
void SortArray(double nums[])
{
    int i, med;
    double brief;

    for (i = ArraySize-1; i >= 0; i--)
    {
        for (med = 1; med <= i; med++)
        {

        if (nums[med-1] > nums[med])
        {
        brief = nums[med-1];
        nums[med-1] = nums[med];
        nums[med] = brief;
        }

        }
    }
}