Why deletion of elements of hash table using doubly-linked list is O(1)?

The problem presented here is : consider you have are looking at a particular element of a hashtable. How costly is it to delete it?

In general you are correct - the algorithm you posted takes an element itself as input though and not just its key.

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.