PHP Exercises: Create a new string where 'if' is added to the front of a given string

PHP Basic Algorithm: Exercise-5 with Solution

Write a PHP program to create a new string where 'if' is added to the front of a given string. If the string already begins with 'if', return the string unchanged.

Sample Solution:

PHP Code :

<?php
// Define a function named "test" that takes a parameter $s
function test($s)
{
    // Check if the length of $s is greater than or equal to 2 AND if the substring of $s from index 0 to 1 is equal to "if"
    if (strlen($s) >= 2 && substr($s, 0, 2) == "if")
    {
        // If true, return $s as it is
        return $s;
    }

    // If false, prepend "if " to $s and return the result
    return "if " . $s;
}

// Call the test function with argument "if else" and echo the result
echo test("if else") . "\n";

// Call the test function with argument "else" and echo the result
echo test("else") . "\n";

// Call the test function with argument "if" and echo the result
echo test("if") . "\n";
?>

Sample Output:

if else
if else
if

Flowchart:

PHP Code Editor:

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