array_intersect < PHP

The array_intersect function returns an array containing all the values from the first array that are present in any of the other arrays.

    
    $colors_fall = array("a"=>"red","b"=>"green","c"=>"blue","d"=>"yellow");
    $colors_spring = array("e"=>"red","f"=>"green","g"=>"blue");

    $colors_intersect = array_intersect($colors_fall,$colors_spring);

    print_r($colors_intersect);
    // Array ( [a] => red [b] => green [c] => blue )