Find or Search array

Hello Sir/Madam,

I wrote a “Find” array in server side, but it dose not work! could you tell me please, what part is false?

<?php 

$GLOBALS['SERVER_SIDE_EQUATIONS']['equation_23'] = array($p1)('222', '333', '444'); 

//search element 
$item = '$p1'; 
if(in_array($item, $p1)){ 
        //the item is there 
    return "ok"; 
} 
else{ 
        //the item isn't there 
    return "null"; 
} 
?> 

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