3v4l.org

run code in 300+ PHP versions simultaneously
<?php $array = array ( // Sub-array 1 array ( // Story 'Monkey 1' - Has identical sub-sub-arrays 'Monkey 2' and 'Monkey 3' and will be merged with them. array ( "header" => "This is a story about a monkey.", 'keywords' => array( "Trees", "Monkey", "Flying", "Drink", "Vacation", "Coconut", "Big", "Bonobo", "Climbing") ), // Story 'Cat 1' - Has identical sub-sub-array 'Cat 2' and will be merged with it. array ( "header" => "Here's a catarific story about a cat", 'keywords' => array( "meauw", "raaaw", "kitty", "growup", "Fun", "claws", "fish", "salmon") ) ), // Sub-array 2 array ( // Story 'Monkey 2' - Has identical sub-sub-arrays 'Monkey 1' and 'Monkey 3' and will be merged with them. array ( "header" => "This is another, but different story, about a monkey.", 'keywords' => array( "Monkey", "Big", "Trees", "Bonobo", "Fun", "Dance", "Cow", "Coconuts") ), // Story 'Cat 2' - Has identical sub-sub-array 'Cat 1' and will be merged with it. array ( "header" => "Here's a different story about a cat", 'keywords' => array( "meauwe", "ball", "cat", "kitten", "claws", "sleep", "fish", "purr") ) ), // Sub-array 3 array ( // Story 'Monkey 3' - Has identical sub-sub-arrays 'Monkey 1' and 'Monkey 2' and will be merged with them. array ( "header" => "This is a third story about a monkey.", 'keywords' => array( "Jungle", "tree", "monkey", "Bonobo", "Fun", "Dance", "climbing", "Coconut", "pretty") ), // Story 'Fireman 1' - Has no identical sub-sub-arrays and will not be merged. array ( "header" => "This is a story about a fireman", 'keywords' => array( "fire", "explosion", "burning", "rescue", "happy", "help", "water", "car") ) ) ); $new =[]; foreach($array as $subarr){ $new = array_merge($new, $subarr); } var_dump($new);

preferences:
46.75 ms | 402 KiB | 5 Q