#import <Foundation/Foundation.h>

 @protocol show

 @required

 -(void)printOn;

 @end

 @interface XYPoint : NSObject<show>{

     int x;

     int y;

 }

 @property (nonatomic,assign)int x,y;

 -(id)setX:(int)_x andY:(int)_y;

 @end

 #import "XYPoint.h"

 @implementation XYPoint

 @synthesize x,y;

 -(id)setX:(int)_x andY:(int)_y{

     self.x=_x;

     self.y=_y;

     return self;

 }

 -(void)printOn{

     NSLog(@"x = %d ,y = %d",x,y);

 }

 @end

 #import <Foundation/Foundation.h>

 #import "XYPoint.h"

 @interface Circle : XYPoint<show>{

     int radius;

 }

 @property (nonatomic,assign)int radius;

 -(id)initWithX:(int)_x andY:(int)_y andRadius:(int)_r;

 -(double)area;

 -(double)perimeter;

 @end

 #import "Circle.h"

 @implementation Circle

 @synthesize radius;

 -(id)initWithX:(int)_x andY:(int)_y andRadius:(int)_r;

 {

     self.x=_x;

     self.y=_y;

     self.radius=_r;

     return self;

 }

 -(double)area{

     return 3.14*radius*radius;

 }

 -(double)perimeter{

     return *,*radius;

 }

 -(void)printOn{

     NSLog(@"x = %d, y = %d ,radius = %d",x,y,radius);

 }

 @end