PHP Array Exercises : Get the last value of an array without affecting the pointer

Last update on May 30 2022 11:42:05 (UTC/GMT +8 hours)

PHP Array: Exercise-50 with Solution

Write a PHP script to get the last value of an array without affecting the pointer.

Sample Solution:

PHP Code:

<?php
$colors = array('c1' => 'Red',  'c2' => 'Green',  'c3' => 'White',  'c4' => 'Black'); 
echo next($colors)."\n";  
$last = array_pop(array_keys(array_flip($colors)));
echo $last."\n";   
echo current($colors)."\n";  
?>

Sample Output:

Green                                                       
Black                                                       
Green

Flowchart:

PHP Code Editor:

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Previous: Write a PHP script to get an array containing all the entries of an array which have the keys that are present in another array.
Next: Write a PHP program to filter out some array elements with certain key-names.

What is the difficulty level of this exercise?

Test your Programming skills with w3resource's quiz.

PHP: Tips of the Day

How to Sort Multi-dimensional Array by Value?

Try a usort, If you are still on PHP 5.2 or earlier, you'll have to define a sorting function first:

Example:

function sortByOrder($a, $b) {
    return $a['order'] - $b['order'];
}

usort($myArray, 'sortByOrder');

Starting in PHP 5.3, you can use an anonymous function:

usort($myArray, function($a, $b) {
    return $a['order'] - $b['order'];
});

And finally with PHP 7 you can use the spaceship operator:

usort($myArray, function($a, $b) {
    return $a['order'] <=> $b['order'];
});

To extend this to multi-dimensional sorting, reference the second/third sorting elements if the first is zero - best explained below. You can also use this for sorting on sub-elements.

usort($myArray, function($a, $b) {
    $retval = $a['order'] <=> $b['order'];
    if ($retval == 0) {
        $retval = $a['suborder'] <=> $b['suborder'];
        if ($retval == 0) {
            $retval = $a['details']['subsuborder'] <=> $b['details']['subsuborder'];
        }
    }
    return $retval;
});

If you need to retain key associations, use uasort() - see comparison of array sorting functions in the manual

Ref : https://bit.ly/3i77vCC