uiviewcontroller - iOS - Using dealloc to remove observer -

i have basic question regarding removing observer.

i have viewcontroller parent class inherited 3 viewcontroller child classes. eg. bookvc -> bookhotelvc, bookflightvc, booktrainvc

here, added observer in viewdidload of parent class (i [super viewdidload] in child viewcontrollers) notifies method written in parent class. code-

[[nsnotificationcenter defaultcenter] addobserver:self selector:@selector(bookingcompleted:) name:@"bookingcompleted" object:nil]; 

now want remove observer when move away of child viewcontrollers, can't write [super dealloc] in dealloc of each child viewcontroller because arc doesn't permit this.

how can remove observer set ? because whenever move child viewcontroller, new observer added causes weird things (like, calling method twice/thrice... - invoking alert twice/thrice...).

kindly suggest.

removing observers in dealloc fine, not call [super dealloc] (as saw, arc enabled, compiler won't let you), write:

- (void)dealloc {     [self removeyourobservers]; }