Merge pull request wangzheng0822#289 from git-zjx/patch-3

Update main.php

Author: wangzheng0822

php/07_linkedlist/main.php

@@ -191,7 +191,7 @@ public function deleteLastKth($index)
  ++$i;
  }
 
- if ($fast == null) {
+ if (null == $fast) {
  return true;
  }
 
@@ -305,4 +305,4 @@ public function findMiddleNode()
 $listAlgo->setList($list);
 $middleNode = $listAlgo->findMiddleNode();
 var_dump($middleNode->data);
-echo '-------------------------------------------------------------'. PHP_EOL . PHP_EOL;
+echo '-------------------------------------------------------------'. PHP_EOL . PHP_EOL;