text: //
  //  DJStack.h
  //  MyStudy
  //
  //  Created by jolin on 2019/10/1.
  //  Copyright © 2019年 jolin. All rights reserved.
  //
  
  #import <Foundation/Foundation.h>
  
  @interface DJStack : NSObject
  
  - (void)push:(void *)obj;
  
  - (void *)pop;
  
  - (BOOL)empty;
  
  @end
  