NSMutableArray计数方法显示，NSMutableArray的计数是0?

This is my init method:

这是我的init方法:

-(id)init{

    self = [super init];
    magicNumber = 8;

    myMagicArray = [[NSMutableArray alloc] initWithCapacity:(magicNumber*magicNumber)];
    NSLog(@"this is the magic Array: %d", [myMagicArray count]);

    return self;
}
-(id)in