PHP Exercises: Count the string "aa" in a given string and assume "aaa" contains two "aa"

PHP Basic Algorithm: Exercise-27 with Solution

Write a PHP program to count the string "aa" in a given string and assume "aaa" contains two "aa".

Sample Solution:

PHP Code :

<?php
// Define a function that counts the occurrences of the substring "aa" in the input string
function test($s)
{
    // Initialize a counter for occurrences of "aa"
    $ctr_aa = 0;

    // Iterate through the string, checking for occurrences of "aa"
    for ($i = 0; $i < (strlen($s) - 1); $i++) {
        if (substr($s, $i, 2) == "aa") {
            $ctr_aa++;
        }
    }

    // Return the count of occurrences
    return $ctr_aa;
}

// Test the function with different input strings
echo test("bbaaccaag") . "\n";
echo test("jjkiaaasew") . "\n";
echo test("JSaaakoiaa") . "\n";
?>

Sample Output:

2
2
3

Pictorial Presentation:

Flowchart:

PHP Code Editor:

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