PHP Array Exercises : Get an array of all elements which have the keys that are present in another array

PHP Array: Exercise-49 with Solution

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.

Sample Solution:

PHP Code:

<?php
// Original associative array
$first_array = array('c1' => 'Red', 'c2' => 'Green', 'c3' => 'White', 'c4' => 'Black'); 

// Array containing keys to check for intersection
$second_array = array('c2', 'c4'); 

// Use array_flip to swap keys and values, then apply array_intersect_key to find common keys
$result = array_intersect_key($first_array, array_flip($second_array));

// Display the result
print_r($result);

?>

Output:

Array                                                       
(                                                           
    [c2] => Green                                           
    [c4] => Black                                           
) 

Flowchart:

PHP Code Editor:

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