PHP Exercises: Check a positive integer and return true if it contains a number 2

Last update on May 28 2025 13:06:59 (UTC/GMT +8 hours)

135. Check if Integer Contains Digit 2

Write a PHP program to check a positive integer and return true if it contains a number 2.

Sample Solution:

PHP Code :

<?php
// Define a function named 'test' that takes an integer 'n'
function test($n)
{ 
    // Use a while loop to iterate as long as 'n' is greater than 0
    while ($n > 0)
    {
        // Check if the last digit of 'n' is equal to 2
        if ($n % 10 == 2)
        {
            // If true, return true, indicating the presence of digit 2
            return true;
        }

        // Remove the last digit from 'n' by dividing it by 10
        $n /= 10;
    }

    // If the loop completes without finding digit 2, return false
    return false;
}

// Use var_dump to display the result of the 'test' function for different inputs
var_dump(test(123));
var_dump(test(13));
var_dump(test(222));
?>

Sample Output:

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

Flowchart:

For more Practice: Solve these Related Problems:

Write a PHP script to determine if a positive integer contains the digit 2 by converting it to a string and searching.
Write a PHP function to scan each digit of an integer and return true if any digit equals 2.
Write a PHP program to use strpos() on a string representation of an integer to detect the presence of the digit 2.
Write a PHP script to implement a loop that checks each digit of an integer for the value 2 and outputs a boolean result.

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