Get startedGet started for free

Implementing the pop method for a stack

In this exercise, you will implement the pop() operation for a stack. pop() will be used to remove an element from the top of the stack. Again, we will consider the size attribute to know the number of elements in the stack.

Recall the Node() class:

class Node:
  def __init__(self, data):
    self.data = data
    self.next = None

This exercise is part of the course

Data Structures and Algorithms in Python

View Course

Hands-on interactive exercise

Have a go at this exercise by completing this sample code.

class Stack:
  def __init__(self):
    self.top = None
    self.size = 0
    
  def pop(self):
    # Check if there is a top element
    if self.____ is None:
      return None
    else:
      popped_node = self.top
      # Decrement the size of the stack
      self.size -= ____
      # Update the new value for the top node
      self.top = self.____
      popped_node.next = None
      return popped_node.data 
Edit and Run Code