返回根页面vc用 ：
[self.navigationController popToRootViewControllerAnimated:NO];
返回指定的某个vc用下面（通过index定位）：
[self.navigationController popToViewController [self.navigationController.viewControllers objectAtIndex:2] animated:YES];
或（通过class定位）：
for (UIViewController *controller in self.navigationController.viewControllers) {
if ([controller isKindOfClass:[你要跳转到的Controller class]]) {
[self.navigationController popToViewController:controller animated:YES];
}
}
