comefrom: <awangdev>239. Sliding Window Maximum_4.java
code: private void outQueue(Deque<Integer> deque, int num) {
  
          if (deque.peekFirst() == num) deque.pollFirst();
      }
masked: private void var_0 ( Deque < Integer > var_3 , int var_4 ) {
    if ( var_3 . peekFirst ( ) == var_4 ) var_3 . pollFirst ( ) ;
  }
  