CS216 Lab1 [3]

#include <iostream>
#include <iomanip>
#include <fstream>

using namespace std;

#define ARR_MAX 50

void inputData(ifstream& inFile, int& evens[], int& odds[], int& evenElements, int& oddElements);
void bubbleSort(int arr[], int elements);
int calcSum(int arr[], int elements);
int calcMedian(int arr[], int elements);
void outputArray(ofstream outFile, int arr[], int elements);
void displayHighestValues(int arr[], int elements, int userValue);
void displayLowestValues(int arr[], int elements, int userValue);
void runtimeError(const string errorMessage);

int main()
{
    int evens[ARR_MAX], odds[ARR_MAX], evenElements = 0, oddElements = 0, userMenuSelection = 0;
    ifstream inFile;
    ofstream outFile;

    inFile.open ("...");

    if (!inFile)
    {
        runtimeError("Failed to open input file.");
    }

    inputData(inFile, evens[], odds[], evenElements, oddElements);
    bubbleSort(evens[], evenElements);
    bubbleSort(odds[], oddElements);

    inFile.close(); //here or at end of main()?

    cout << "[1] Display the number of entries and totals of each list.\n"
         << "[2] Display the averages of each list.\n"
         << "[3] Display the medians of each list.\n"
         << "[4] Output sorted lists to file.\n"
         << "[5] Display the highest X values of each list.\n"
         << "[6] Display the lowest X values of each list.\n"
         << "[7] Exit.\n";

    do
    {
        int evenSum, oddSum, evenMedian, oddMedian, userMenuSelection;
        bool sumCalculated = 0, medianCalculated = 0;

        if (userMenuSelection)
        {
            cout << "Select another option.\n";
        }
        else
        {
            cout << "Select an option by entering its corresponding number.\n";
        }

        cin >> userMenuSelection;

        switch(userMenuSelection)
        {
            case 1:
                if (!sumCalculated)
                {
                    evenSum = calcSum(evens[], evenElements);
                    oddSum = calcSum(odds[], oddElements)
                    sumCalculated = 1;
                }

                cout << "# of Even entries: " << evenElements << endl
                     << "# of Odd Entries: " << oddElements << endl
                     << "Sum of Even List: " << evenSum << endl
                     << "Sum of Odd List: " << oddSum;
                break;
            case 2:
                cout << "Average of Even List: " << (float) evenSum / evenElements << endl
                     << "Average of Odd List: " << (float) oddSum / oddElements;
                break;
            case 3:
                if (!medianCalculated)
                {
                    evenMedian = calcMedian(evens[], evenElements);
                    oddMedian = calcMedian(odds[], oddElements)
                    medianCalculated = 1;
                }

                cout << "Median of Even List: " << evenMedian << endl
                     << "Median of Odd List: " << oddMedian;
                break;
            case 4:
                outFile.open ("...");

                outFile << "Even List:\n";
                outputArray(outFile, evens[], evenElements);
                outFile << "Odd List:\n";
                outputArray(outFile, odds[], oddElements);

                outFile.close();
                break;
            case 5:
                cout << "Enter a value for X: ";
                cin >> userValue;

                cout << "Highest " << userValue << " Even Values: "
                displayHighestValues(evens[], evenElements, userValue);
                cout << "Highest " << userValue << " Odd Values: "
                displayHighestValues(odds[], oddElements, userValue);
                break;
            case 6:
                cout << "Enter a value for X: ";
                cin >> userValue;

                cout << "Lowest " << userValue << " Even Values: "
                displayLowestValues(evens[], evenElements, userValue);
                cout << "Lowest " << userValue << " Odd Values: "
                displayLowestValues(odds[], oddElements, userValue);
                break;
            case 7:
                cout << "Exiting program.\n";
                break;
            default:
                cout << "Invalid menu option selected.\n";
                break;
        }
    } while (userChoice != 7);

    return 0;
}

void inputData(fstream& inFile, int& evens[], int& odds[], int& evenElements, int& oddElements)
{
    int value;

    for (int i = 0; evenElements < ARR_MAX && oddElements < ARR_MAX && !feof(inFile); ++i)
    {
        inFile >> value;

        if (value % 2 == 0)
        {
            evens[evenElements++] = value;
        }
        else
        {
            odds[oddsElements++] = value;
        }
    }

    if (evenElements == 0 && oddElements == 0)
    {
        runtimeError("Input file is empty.");
    }
    if (!feof(inFile))
    {
        runtimeError("Excess entries detected.");
    }
}

void bubbleSort(int arr[], int elements)
{
    int elmnt1, elmnt2;

    for (elmnt1 = 0; elmnt1 < elements - 1; ++elmnt1)
    {
        for (elmnt2 = 0; elmnt2 < elements - elmnt1 - 1; ++elmnt2)
        {
            if (arr[elmnt2] > arr[elmnt2 + 1])
            {
                int temp = arr[elmnt2];
                arr[elmnt2] = arr[elmnt2 + 1];
                arr[elmnt2 + 1] = temp;
            }
        }
    }
}

int calcSum(int arr[], int elements)
{
    int sum = 0;

    for (int i = 0; i < elements; ++i)
    {
        sum += arr[i];
    }

    return sum;
}

int calcMedian(int arr[], int elements)
{
    if (elements % 2 == 0)
    {
        return (float )(arr[elements / 2] + arr[(elements / 2) + 1]) / 2;
    }
    else
    {
        return arr[(elements / 2) + 1];
    }
}

void outputArray(ofstream outFile, int arr[], int elements)
{
    for (int i = 0; i < elements; ++i)
    {
        outFile << arr[i] << ' ';
    }
}

void displayHighestValues(int arr[], int elements, int userValue);
{
    for (int i = 0; i < userValue; ++i)
    {
        cout << arr[elements - 1 - i] << ' ';
    }
}

void displayLowestValues(int arr[], int elements, int userValue)
{
    for (int i = 0; i < userValue; ++i)
    {
        cout << arr[i] << ' ';
    }
}

void runtimeError(const string errorMessage)
{
    cout << "Error: " << errorMessage << " Exiting program.\n";
    exit(1);
}