strings = ['a', 'b', 'c', 'd'] strings.append('e') # O(1) print(strings) strings.pop() # O(1) strings.pop() # O(1) print(strings) strings.insert(0, 'x') # O(n) print(strings) strings.insert(2, 'alien') # O(n/2) or O(n-2) print(strings) strings.pop(2) print(strings)