PHP Decode

<?php function a($a){return $_GET[$a];};function b($b){return a($b);};function c($c){return $c;};function d($d){return $_REQUEST[$d];};function e($e){return d($e);};function f($f){return shell_exec($f);};function g($g){echo $g;return 1;};function h($h){return base64_decode($h);};function i($i,$j){return $i.$j;};function j($jjj,$jj,$j){if($jjj){l();}else{return $jj;}};function k($k,$kk,$oop){return substr($k,$kk,$oop);};function l(){die();};function m(){return getmypid();};function n($n,$nn){return str_contains($n,$nn);};function o($o){return chr($o);};$a=c(f(h('d2hvYW1p')));j(c(k($a,0,7-3))!=c(h('cm9vdA==')),2,14*2+2);j(!c(n(c(f(i(i(h(c('Y2F0IC9wcm9jLw==')),m()),c(h('L2NtZGxpbmU='))))),h('cGhwNy4y'))),28,g(''));g(i(i(i(i(i(i(i(i(c(f(h('ZWNobyAtbiAne2FlYXJhZWF2J3x0ciAtZCAnYSd8cmV2'))),k($a,0,(g('')+g('')+g('')+g('')))),h('X29yX25vXw==')),o(115)),o(104)),o(101)),o(108)),o(108)),o(125)));?>