array compare values code example

Example 1: array_diff

<?php
$array1 = array("a" => "green", "red", "blue", "red");
$array2 = array("b" => "green", "yellow", "red");
$result = array_diff($array1, $array2);
?>

Array
(
    [1] => blue
)

Example 2: how to compare elements in an array

for (let i = 0; i < a.length; i++) {
    for (let k = i + 1; k < a.length; k++) {
        if (a[i] != a[k]) {
            //do stuff
        }
    }
}