How to Quickly Remove Items From a List

Question

I am looking for a way to quickly remove items from a C# List. The documentation states that the List.Remove() and List.RemoveAt()<

Answer 1

You could always remove the items from the end of the list. List removal is O(1) when performed on the last element since all it does is decrement count. There is no shifting of next elements involved. (which is the reason why list removal is O(n) generally)

for (int i = list.Count - 1; i >= 0; --i)
  list.RemoveAt(i);