Stack implementation using List(Python)
The functions associated with stack are:
empty() – Returns whether the stack is empty – Time Complexity: O(1)
size() – Returns the size of the stack – Time Complexity: O(1)
top() / peek() – Returns a reference to the topmost element of the stack – Time Complexity: O(1)
push(a) – Inserts the element ‘a’ at the top of the stack – Time Complexity: O(1)
pop() – Deletes the topmost element of the stack – Time Complexity: O(1)