NSArray *array = [NSArray arrayWithObjects:@"1",@"2",@"3",nil];

    [array enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {

        NSLog(@"%zi->%@",idx, obj);

    }];


    NSMutableString *string1 = [NSMutableString stringWithString:@"A"];

    NSMutableString *string2 = [NSMutableString stringWithString:@"B"];

    NSMutableString *string3 = [NSMutableString stringWithString:@"C"];

    

    NSArray *listOfObjects = [NSArray arrayWithObjects:string1, string2,string3, nil];

    

    for(NSMutableString *s in listOfObjects){

        NSLog(@"This string in lowercase is %@", [s lowercaseString]);

        

    }

    

    [listOfObjects makeObjectsPerformSelector:@selector(appendString:)withObject:@"-MORE"];