I don't mean to be rude, but this is really well documented. A google search or even an Apple documentation search on UINavigationController will turn up exactly what you need. To programmatically pop the current view controller you use:
[[self navigationController] popViewControllerAnimated:YES];
To pop to a specific view controller, you use:
[[self navigationController] popToViewController:controller animated:YES];
You will have to iterate through the list of view controllers first and check the title against what you're looking for and pass that to this method.
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