Objective-c语言_使用字符串然后retainCount会出现一长串数字

NSString *string=[NSString
stringWithFormat:@"ppp"];

NSString *string1=[string
copy];

if (string==string1)

{

NSLog(@"string=%lu:string1=%lu",[string
retainCount],[string1
retainCount]);

}

//不可变字符串在stringWithFormat后是不能被引用计数

NSMutableString *mstring=[NSMutableString
stringWithFormat:@"ddd"];

NSMutableString *mstring1=[mstring
copy];

NSLog(@"mstring=%lu:mstring1=%lu",[mstring
retainCount],[mstring1
retainCount]);

//可变字符串在stringWithFormat后能被引用计数

运行结果：