61，对象作为返回值

#import

@interface Gun : NSObject

-(void)about;

@end

@implementation Gun

-(void)about{

    NSLog(@"这是一把冲锋枪");

}

@end

@interface Shop : NSObject

+(Gun *) buyGun:(int)money;

@end

@implementation Shop

+(Gun *) buyGun:(int)money{

    Gun *gun;

    if (money > 100) {

        gun = [Gun new];

    }

    return gun;

}

@end

int main(int argc,const char * argv[]) {

    @autoreleasepool {

        Gun *gun = [ShopbuyGun:101];

        [gun about];

    }

    return 0;

}

//2015-12-05 22:55:35.409 4，对象作为返回值[2193:302363]这是一把冲锋枪

//Program ended with exit code: 0