PHP Exercises: Count number of vowels in a given string

Last update on April 19 2025 11:50:14 (UTC/GMT +8 hours)

96. Count Vowels in a String

Write a PHP program to count number of vowels in a given string.

Note: Use a regular expression to count the number of vowels (A, E, I, O, U) in a string.

Sample Solution:

PHP Code:

<?php
// Licence: https://bit.ly/2CFA5XY

// Function definition for 'count_Vowels' that takes a string as a parameter
function count_Vowels($string)
{
    // Use 'preg_match_all' with a regular expression to find all vowels (case-insensitive) in the string
    preg_match_all('/[aeiou]/i', $string, $matches);

    // Return the count of matched vowels found in the string
    return count($matches[0]);
}

// Call 'count_Vowels' with a string and display the result using 'print_r'
print_r(count_Vowels('sampleInput'));

?>

Explanation:

Function Definition:

The count_Vowels function takes a single parameter:

$string: the input string in which to count vowels.

Finding Vowels:

The function uses preg_match_all with the regular expression /[aeiou]/i:

[aeiou]: matches any vowel (a, e, i, o, u).
/i: makes the matching case-insensitive, so it includes both uppercase and lowercase vowels.

The matching vowels are stored in $matches.

Count Matched Vowels:

count($matches[0]) returns the number of vowels found in $string.

Function Call and Output:

count_Vowels('sampleInput') counts the vowels in 'sampleInput' and outputs the result using print_r.

Output:

Flowchart:

For more Practice: Solve these Related Problems:

Write a PHP script to count the number of vowels in a string using regular expressions with case insensitivity.
Write a PHP function to iterate over each character in a string and tally vowels found.
Write a PHP script to compute the total number of vowels in an input sentence by filtering characters.
Write a PHP script to use preg_match_all to count occurrences of A, E, I, O, U in a provided string.

PHP Code Editor:

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