PHP Exercises: Deep flatten an given array
PHP: Exercise-79 with Solution
Write a PHP program to deep flatten an given array.
Sample Solution: -
PHP Code:
<?php
function deep_flatten($items)
{
$result = [];
foreach ($items as $item) {
if (!is_array($item)) {
$result[] = $item;
} else {
$result = array_merge($result, deep_flatten($item));
}
}
return $result;
}
$result = deep_flatten([1, [2], [[3], 4], 5, 6]);
print_r($result);
?>
Sample Output:
Array ( [0] => 1 [1] => 2 [2] => 3 [3] => 4 [4] => 5 [5] => 6 )
Flowchart:

PHP Code Editor:
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Previous: Write a PHP program to create a function that returns true for all elements of an array, false otherwise.
Next: Write a PHP program to create a new array with n elements removed from the left.
What is the difficulty level of this exercise?
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PHP: Tips of the Day
Returns all elements in an array except for the first one
Example:
<?php function tips_tail($items) { return count($items) > 1 ? array_slice($items, 1) : $items; } print_r(tips_tail([1, 5, 7])); ?>
Output:
Array ( [0] => 5 [1] => 7 )
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