Find size of Doubly Linked List

class Nodes:

def __init__(self):

self.data = None

self.next = None

self.prev = None

def push( ref, new_data):

new_node = Nodes()

new_node.data = new_data

new_node.next = (ref)

new_node.prev = None

if ((ref) != None):

(ref).prev = new_node

(ref) = new_node

return ref

def findSize(node):

res = 0

while (node != None):

res = res + 1

node = node.next

return res

head = None

head = push(head, 4)

head = push(head, 3)

head = push(head, 2)

head = push(head, 1)

print(findSize(head))

Spiral Square Mania with Turtle

import turtle as t

pen = t.Turtle()

pen.color("cyan")

pen.speed(0)

colors = ["green","black","orange","navy","green","black","orange","navy"]

def draw_square(color):

        for side in range(4):

                pen.forward(100)

                pen.right(90)

                for side in range(4):

                        pen.forward(50)

                        pen.right(90)

pen.penup()

pen.back(40)

pen.pendown()

for color in colors:

        pen.color(color)

        draw_square(color)

        pen.forward(50)

        pen.left(45)

pen.hideturtle()

t.done()

Chess-Board using Turtle

import turtle

sc = turtle.Screen()

cb = turtle.Turtle()

def draw():

    for i in range(4):

        cb.forward(30)

        cb.left(90)

    cb.forward(30)

if __name__ == "__main__":

    sc.setup(400, 600)

    cb.speed(100)

    for i in range(8):

        cb.up()

        cb.setpos(-100, 30 * i)

        cb.down()

        for j in range(8):

            if (i + j) % 2 == 0:

                col = 'black'

            else:

                col = 'white'

            cb.fillcolor(col)

            cb.begin_fill()

            draw()

            cb.end_fill()

    cb.hideturtle()

    turtle.done()

The Story of Python, by Its Creator, Guido van Rossum

Guido van Rossum  is a Dutch programmer best known as the creator of the Python programming language, for which he was the "benevolent dictator for life" (BDFL) until he stepped down from the position on 12 July 2018. He remained a member of the Python Steering Council through 2019, and withdrew from nominations for the 2020 election.

Iterative Method to find Height of Binary Tree

class Node:

def __init__(self, data):

self.data = data

self.left = None

self.right = None

def treeHeight(root):

if root is None:

return 0

q = []

q.append(root)

height = 0

while(True):

nodeCount = len(q)

if nodeCount == 0 :

return height

height += 1

while(nodeCount > 0):

node = q[0]

q.pop(0)

if node.left is not None:

q.append(node.left)

if node.right is not None:

q.append(node.right)

nodeCount -= 1

root = Node(1)

root.left = Node(2)

root.right = Node(3)

root.left.left = Node(4)

root.left.right = Node(5)

print ("Height of tree is", treeHeight(root))