Data structure (Python)

# Course: CS261 - Data Structures # Student Name: # Assignment: # Description: from sll import * class StackException(Exception): """ Custom exception to be used by MaxStack Class DO NOT CHANGE THIS CLASS IN ANY WAY """ pass class MaxStack: def __init__(self): """ Init new MaxStack based on Singly Linked Lists DO NOT CHANGE THIS METHOD IN ANY WAY """ self.sll_val = LinkedList() self.sll_max = LinkedList() def __str__(self) -> str: """ Return content of stack in human-readable form DO NOT CHANGE THIS METHOD IN ANY WAY """ out = "MAX STACK: " + str(self.sll_val.length()) + " elements. " out += str(self.sll_val) return out def is_empty(self) -> bool: """ Return True is Maxstack is empty, False otherwise DO NOT CHANGE THIS METHOD IN ANY WAY """ return self.sll_val.is_empty() def size(self) -> int: """ Return number of elements currently in the MaxStack DO NOT CHANGE THIS METHOD IN ANY WAY """ return self.sll_val.length() # ------------------------------------------------------------------ # def push(self, value: object) -> None: """ TODO: Write this implementation """ pass def pop(self) -> object: """ TODO: Write this implementation """ pass def top(self) -> object: """ TODO: Write this implementation """ pass def get_max(self) -> object: """ TODO: Write this implementation """ pass # BASIC TESTING if __name__ == "__main__": pass # print('\n# push example 1') # s = MaxStack() # print(s) # for value in [1, 2, 3, 4, 5]: # s.push(value) # print(s) # # # print('\n# pop example 1') # s = MaxStack() # try: # print(s.pop()) # except Exception as e: # print("Exception:", type(e)) # for value in [1, 2, 3, 4, 5]: # s.push(value) # for i in range(6): # try: # print(s.pop()) # except Exception as e: # print("Exception:", type(e)) # # # print('\n# top example 1') # s = MaxStack() # try: # s.top() # except Exception as e: # print("No elements in stack", type(e)) # s.push(10) # s.push(20) # print(s) # print(s.top()) # print(s.top()) # print(s) # # print('\n# get_max example 1') # s = MaxStack() # for value in [1, -20, 15, 21, 21, 40, 50]: # print(s, ' ', end='') # try: # print(s.get_max()) # except Exception as e: # print(type(e)) # s.push(value) # while not s.is_empty(): # print(s.size(), end='') # print(' Pop value:', s.pop(), ' get_max after: ', end='') # try: # print(s.get_max()) # except Exception as e: # print(type(e))