1#import <UIKit/UIKit.h>
 2
 3@class Brain;
 4
 5@interface ViewController : UIViewController
 6@property (strong, nonatomic) IBOutlet UILabel * display;
 7@property (strong, nonatomic) Brain * myBrain;
 8-(IBAction) numberPressed:(id)sender;
 9-(IBAction) operationPressed:(id)sender;
10-(IBAction) enterPressed:(id)sender;
11-(IBAction) clearPressed:(id)sender;
12@end