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PHP Exercises: Check if the first appearance of "a" in a given string is immediately followed by another "a"

PHP Basic Algorithm: Exercise-28 with Solution

Write a PHP program to check if the first appearance of "a" in a given string is immediately followed by another "a".

Sample Solution:

PHP Code :

<?php
// Define a function that checks for the presence of at least two consecutive 'a's in a string
function test($s)
{
    // Initialize a counter for 'a' occurrences
    $counter = 0;

    // Iterate through the string
    for ($i = 0; $i < strlen($s) - 1; $i++) {
        // Check for 'a' and increment the counter
        if (substr($s, $i, 1) == 'a') {
            $counter++;
        }

        // Check for 'aa' and if counter is less than 2, return true
        if ((substr($s, $i, 2) == 'aa') && $counter < 2) {
            return true;
        }
    }

    // If no condition met, return false
    return false;
}

// Test the function with different input strings
var_dump(test("caabb"));
var_dump(test("babaaba"));
var_dump(test("aaaaa"));
?>

Sample Output:

bool(true)
bool(false)
bool(true)

Visual Presentation:

PHP Basic Algorithm Exercises: Check if the first appearance of 'a' in a given string is immediately followed by another 'a'.

Flowchart:

Flowchart: Check if the first appearance of 'a' in a given string is immediately followed by another 'a'.

PHP Code Editor:

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Previous: Write a PHP program to count the string "aa" in a given string and assume "aaa" contains two "aa".
Next: Write a PHP program to create a new string made of every other character starting with the first from a given string.

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