X

C Program to Check Whether a Character is a Vowel or Consonant

In this example, you will learn to check whether an alphabet entered by the user is a vowel or a consonant.

Limited time offer: Get 10 free Adobe Stock images.ADS VIA CARBON

To understand this example, you should have the knowledge of the following C programming topics:


The five letters A, E, I, O and U are called vowels. All other alphabets except these 5 vowels are called consonants.

This program assumes that the user will always enter an alphabet character.


Program to Check Vowel or consonant

#include int main() { char c; int lowercase_vowel, uppercase_vowel; printf("Enter an alphabet: "); scanf("%c", &c); // evaluates to 1 if variable c is a lowercase vowel lowercase_vowel = (c == 'a' || c == 'e' || c == 'i' || c == 'o' || c == 'u'); // evaluates to 1 if variable c is a uppercase vowel uppercase_vowel = (c == 'A' || c == 'E' || c == 'I' || c == 'O' || c == 'U'); // evaluates to 1 (true) if c is a vowel if (lowercase_vowel || uppercase_vowel) printf("%c is a vowel.", c); else printf("%c is a consonant.", c); return 0; }

Output

Enter an alphabet: G
G is a consonant.

The character entered by the user is stored in variable c.

The lowercase_vowel variable evaluates to 1 (true) if c is a lowercase vowel and 0 (false) for any other characters.

Similarly, the uppercase_vowel variable evaluates to 1 (true) if c is an uppercase vowel and 0 (false) for any other character.

If either lowercase_vowel or uppercase_vowel variable is 1 (true), the entered character is a vowel. However, if both lowercase_vowel and uppercase_vowel variables are 0, the entered character is a consonant.

Note: This program assumes that the user will enter an alphabet. If the user enters a non-alphabetic character, it displays the character is a consonant.

To fix this, we can use the isalpha() function. The islapha() function checks whether a character is an alphabet or not.

#include #include int main() { char c; int lowercase_vowel, uppercase_vowel; printf("Enter an alphabet: "); scanf("%c", &c); // evaluates to 1 if variable c is a lowercase vowel lowercase_vowel = (c == 'a' || c == 'e' || c == 'i' || c == 'o' || c == 'u'); // evaluates to 1 if variable c is a uppercase vowel uppercase_vowel = (c == 'A' || c == 'E' || c == 'I' || c == 'O' || c == 'U'); // Show error message if c is not an alphabet if (!isalpha(c)) printf("Error! Non-alphabetic character."); else if (lowercase_vowel || uppercase_vowel) printf("%c is a vowel.", c); else printf("%c is a consonant.", c); return 0; }

Now, if the user enters a non-alphabetic character, you will see:

Enter an alphabet: 3
Error! Non-alphabetic character.
Categories: Uncategorized
ilexjjtt-ca: