NSString *type = @"hello";
NSString *subtype = @"good";
NSString *typesub = [NSString stringWithFormat:@"%@>%@",type,subtype];
NSString *typesub1 = [type stringByAppendingString:subtype];
NSString *typesub2 = [type stringByAppendingFormat:@"%@>%@",type,subtype];
NSString *a= @"abc" ;
NSString *typesub3 = [type stringByAppendingFormat:@"%@>%@>%@" ,type,subtype,a];
NSLog(@"%@,%@,%@,%@",typesub,typesub1,typesub2,typesub3,typesub3);