PHP Array Exercises : Lower-case and upper-case, all elements in an array

PHP Array: Exercise-36 with Solution

Write a PHP script to lower-case and upper-case, all elements in an array.

Sample Solution:

PHP Code:

$colors = array( "Red", "Green", "Black", "White"); 

$lower_colors = array_map('strtolower', $colors);
$upper_colors = array_map('strtoupper', $colors);

Sample Output:

    [0] => Red                                              
    [1] => Green                                            
    [2] => Black                                            
    [3] => White                                            
    [0] => red                                              
    [1] => green                                            
    [2] => black                                            
    [3] => white                                            
    [0] => RED                                              
    [1] => GREEN                                            
    [2] => BLACK                                            
    [3] => WHITE                                            


Flowchart: PHP - Lower-case and upper-case, all elements in an array

PHP Code Editor:

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PHP stores error logs in /var/log/apache2 if PHP is an apache2 module. Shared hosts are often storing log files in your root directory /log subfolder. But...if you have access to a php.ini file you can do this:

error_log = /var/log/php-scripts.log

According to rinogo's comment: If you're using cPanel, the master log file you're probably looking for is stored (by default) at


If all else fails you can check the location of the log file using

<?php phpinfo(); ?>

Ref : https://bit.ly/2EffgH5


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