Programming Challenge 10.6 - Vowels And Consonants

/* Vowels And Consonants - This program contains a function that accepts
    a pointer to a C-string as its argument. The function counts the number
    of vowels appearing in the string and returns that number.
   
    The second function accepts a pointer to a C-string as its argument.
    It counts the number of consonants appearing in the string and returns
    that number.
   
    The functions are demonstrated by performing the following steps:

        * The user is asked to enter a string.

        * The program displays the following menu:

            * Count the number of vowels in the string
            * Count the number of consonants in the string
            * Count both the vowels and consonants in the string
            * Enter another string
            * Exit the program

        * The program performs the operation selected by the user and
          repeats until the user selects E to exit the program. */

#include "Utility.h"

/* Provides a basic menu */
int menu();

/* Allows the user to make a menu choice,
    returns the menu choice */
int menuOptions();

/* Determines whether a character is a vowel,
    returns the result */
bool vowel(char);

/* Counts the vowels in a C-string,
    returns the number of vowels found */
int countVowels(char *);

/* Counts the consonants in a C-string,
    returns the number of consonants found */
int countConsonants(char *);

int main()
{
    menu();

   pauseSystem();
   return 0;
}

/* **********************************************************
    Definition: menu

    This function provides a basic menu.
   ********************************************************** */

int menu()
{
    const int NUM_WORDS = 200;

    int         numVowels = 0,
                 numConsonants = 0,
                 menuChoice = 0;
    char         sentence[NUM_WORDS];

    cout << "\n\tVOWEL AND CONSONANT COUNT\n\n"
          << "\tEnter a sentence, " << (NUM_WORDS - 1)
          << " characters maximum in length:\n\t";
    cin.getline(sentence, NUM_WORDS);

    do
    {
        menuChoice = menuOptions();
        cin.ignore();

        switch (menuChoice)
        {
            case 1:
            {               
                cout << "\n\tYour sentence contains: "
                      << (numVowels = countVowels(sentence))
                      << " vowels.\n\n";
            }
            break;

            case 2:
            {
                cout << "\n\tYour sentence contains: "
                      << (numConsonants = countConsonants(sentence))
                      << " consonants.\n\n";
            }
            break;

            case 3:
            {
                cout << "\n\tYour sentence contains: "
                      << (numVowels = countVowels(sentence))
                      << " vowels and "
                      << (numConsonants = countConsonants(sentence))
                      << " consonants.\n\n";
            }
            break;

            case 4:
            {
                cout << "\n\tEnter another sentence:\n\t";
                cin.getline(sentence, NUM_WORDS);
            }
            break;

            case 5:
            {
                cout << "\n\tHave a nice day!\n\n";
            }
        }
    } while (menuChoice != 5);

    return 0;
}

/* **********************************************************
    Definition: displayOptions

    This function displays the main menu options.
   ********************************************************** */

int menuOptions()
{
    const int VOWEL_COUNT = 1,
                 CONSONANT_COUNT = 2,
                 VOWEL_CONSONANT_COUNT = 3,
                 AGAIN = 4,
                 EXIT = 5;

    int         menuChoice = 0;

    cout << "\n\tMain Menu\n"
          << "\t----------\n\n"
          << "\t1. Count the number of vowels in the string\n"
          << "\t2. Count the number of consonants in the string\n"
          << "\t3. Count both the vowels and consonants in the string\n"
          << "\t4. Enter another string\n"
          << "\t5. Exit\n\n"
          << "\tEnter your choice: ";
    cin >> menuChoice;

    /* Input validation */
    while (menuChoice < VOWEL_COUNT || menuChoice > EXIT)
    {
        cout << "\tEnter your choice: ";
        cin >> menuChoice;
    }

    return menuChoice;
}

/* **********************************************************
    Definition: isVowel

    This function determines if a character is a vowel. The
    result is returned.
   ********************************************************** */

bool vowel(char vowel)
{
    if (vowel == 'a' || vowel == 'i' || vowel == 'e' || vowel == 'o' ||
         vowel == 'u' || vowel == 'A' || vowel == 'I' || vowel == 'I' ||
         vowel == 'O' || vowel == 'U')
    {
        return true;
    }
    else
    {
        return false;
    }
}

/* **********************************************************
   Definition: countVowels

    This function accepts a C-string object as argument. It
    counts the number of vowels and returns this number.
   ********************************************************** */

int countVowels(char *wordPtr)
{
    unsigned int index = 0,
                     vowelCount = 0;

    for (index = 0; index < strlen(wordPtr); index++)
    {   
        if (vowel(wordPtr[index])==true)
        {   
            ++vowelCount;
        }       
    }

    return vowelCount;
}

/* **********************************************************
   Definition: countConsonants

    This function accepts a C-string object as argument. It
    counts the number of consonants in a sentence and returns
    this number.
   ********************************************************** */

int countConsonants(char *wordPtr)
{
    unsigned int index = 0,
                     consonantCount = 0;
    bool             isConsonant = false;

    for (index = 0; index < strlen(wordPtr); index++)
    {
        if (vowel(wordPtr[index]) == true)
        {
            isConsonant = false;
        }

        else if (isalpha(wordPtr[index]))
        {
            isConsonant = true;
            consonantCount++;
        }   
    }

    return consonantCount;
}

Example Output: