PHP Program to Find Missing Characters to Make a String Pangram

In this article, we will see how to find the missing characters to make the string Pangram using PHP. A pangram is a sentence containing every letter in the English Alphabet.

Examples:

Input: The quick brown fox jumps over the dog
Output: Missing Characters - alyz

Input: The quick brown fox jumps
Output: Missing Characters - adglvyz

PHP Program to Find Missing Characters to Make a String Pangram using for() Loop

The provided PHP code defines a function findMissingCharacters() that takes a string as input and identifies the missing characters required to make it a pangram.

Example: In this example, we will find the missing number to make string pangram.

PHP

<?php

function findMissingCharacters($str) {

      // Convert the string to lowercase
    $str = strtolower($str);

      // Create an array of all lowercase letters
    $alphabet = range('a', 'z');

    $present_chars = [];
    $missing_chars = '';

    // Check each character in the string
    for ($i = 0; $i < strlen($str); $i++) {
        $char = $str[$i];
        if (ctype_alpha($char)) {
            $present_chars[$char] = true;
        }
    }

    // Check for missing characters
    foreach ($alphabet as $letter) {
        if (!isset($present_chars[$letter])) {
            $missing_chars .= $letter;
        }
    }

    return $missing_chars;
}

$str = "The quick brown fox jumps over the dog";
$missing_chars = findMissingCharacters($str);

if (empty($missing_chars)) {
    echo "The string is a pangram.\n";
} else {
    echo "Missing characters: $missing_chars\n";
}

?>

Output

Missing characters: alyz

PHP Program to Find Missing Characters to Make a String Pangram using range() and strpos() Methods

The range() and strpos() methods are used to find the missing number to make the string pangram.

Example:

PHP

<?php

function missingChars($str) {
    $result = "";
    $str = strtolower($str);
    $letters = range('a', 'z');

    foreach ($letters as $char) {
        if (strpos($str, $char) === false) {
            $result .= $char;
        }
    }

    return $result;
}

// Driver code
$inputString =
    "The quick brown fox jumps over the dog";

$missingChars = missingChars($inputString);

if ($missingChars === "") {
    echo "String is a pangram";
} else {
    echo "Missing characters to make the"
    . " string pangram: {$missingChars}";
}

?>

Output

Missing characters to make the string pangram: alyz