How to remove the ChildViewController from Parent View Controller in Swift 3

After the long search to remove the view controllers from viewpager. I did it in the following way.

 if self.childViewControllers.count > 0{
        let viewControllers:[UIViewController] = self.childViewControllers
        for viewContoller in viewControllers{
            viewContoller.willMove(toParentViewController: nil)
            viewContoller.view.removeFromSuperview()
            viewContoller.removeFromParentViewController()
        }
    }

here self is , Current UIViewController which has View Pager. I need to remove all the childview controllers from the view pager. So, i get the list of view controllers from Current UIViewController. Then i removed it from the Parent view.

For swift 4.2

 if self.children.count > 0{
        let viewControllers:[UIViewController] = self.children
        for viewContoller in viewControllers{
            viewContoller.willMove(toParent: nil)
            viewContoller.view.removeFromSuperview()
            viewContoller.removeFromParent()
        }
    }

EDIT

Remove top childview controller:

   func removeTopChildViewController(){
         if self.children.count > 0{
             let viewControllers:[UIViewController] = self.children
                viewControllers.last?.willMove(toParent: nil)
                viewControllers.last?.removeFromParent()
                viewControllers.last?.view.removeFromSuperview()
         }
     }