How to remove duplicate values from a multi-dimensional array in PHP

To remove duplicate values from a multi-dimensional array in PHP, you can use the following approach:

  1. First, convert the multi-dimensional array into a single-dimensional array using array_merge() function.
  2. Then use the array_unique() function to remove the duplicate values from the single-dimensional array.
  3. Finally, convert the single-dimensional array back into a multi-dimensional array using array_chunk() function.

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Here is an example of how you can implement this:

<?php

$input = [[1, 2, 3], [2, 3, 4], [3, 4, 5]];

// Convert the multi-dimensional array into a single-dimensional array
$single_dimensional_array = array_merge(...$input);

// Remove the duplicate values from the single-dimensional array
$single_dimensional_array = array_unique($single_dimensional_array);

// Convert the single-dimensional array back into a multi-dimensional array
$result = array_chunk($single_dimensional_array, count($input[0]));

print_r($result);

The resulting array $result will contain the values of the original array $input with duplicate values removed.