如何在目标c中声明实例变量？

Question

由于我使用“分子”的方式存在问题，我收到此错误和其他许多错误。和分母＆＃39;变量：＆＃34;不一致的实例变量规范＆＃34;

我是Objective C的新手，所以我不确定如何解决这个简单的问题。

#import <Foundation/Foundation.h>

@interface Fraction: NSObject

-(void)   print;
-(void)   setNumerator: (int) n;
-(void)   setDenominator: (int) d;

@end

@implementation Fraction
{
   int  numerator;
   int  denominator;
}
-(void) print
{
   NSLog (@"%i/%i", numerator, denominator);
}

-(void) setNumerator: (int) n
{
   numerator = n;
}

-(void) setDenominator: (int) d
{
   denominator = d;
}

@end

int main (int argc, char * argv[])
{
   @autoreleasepool {
      Fraction  *myFraction;

      myFraction = [Fraction alloc];
      myFraction = [myFraction init];

      [myFraction setNumerator: 1];
      [myFraction setDenominator: 3];

      NSLog (@"The value of myFraction is:");
      [myFraction print];
   }
   return 0;
}