import os

# Get the current directory
current_dir = os.getcwd()

# Loop through each file in the current directory
for filename in os.listdir(current_dir):

    # Check if the file name starts with a number followed by a period and a space
    if filename[0].isdigit() and filename[1] == '.' and filename[2] == ' ':
        
        # Remove the number, period, and space from the file name
        new_filename = filename[3:]
        
        # Rename the file
        os.rename(os.path.join(current_dir, filename), os.path.join(current_dir, new_filename))

my_list = ["blue", "red", "green"]

#1- Using sort or srted directly or with specifc keys
my_list.sort() #sorts alphabetically or in an ascending order for numeric data 
my_list = sorted(my_list, key=len) #sorts the list based on the length of the strings from shortest to longest. 
# You can use reverse=True to flip the order

#2- Using locale and functools 
import locale
from functools import cmp_to_key
my_list = sorted(my_list, key=cmp_to_key(locale.strcoll))

filename = "data.txt"
data = "Hello, World!"

with open(filename, "a") as file:
    file.write(data)

import string

def caesar(text, shift, alphabets):
	def shift_alphabet(alphabet):
	    return alphabet[shift:] + alphabet[:shift]
	
	shifted_alphabets = tuple(map(shift_alphabet, alphabets))
	final_alphabet = "".join(alphabets)
	final_shifted_alphabet = "".join(shifted_alphabets)
	table = str.maketrans(final_alphabet, final_shifted_alphabet)
	return text.translate(table)

plain_text = "Hey Skrome, welcome to CodeCatch"
print(caesar(plain_text, 8, [string.ascii_lowercase, string.ascii_uppercase, string.punctuation]))

my_list = [1, 2, 3, 4, 5]
removed_element = my_list.pop(2)  # Remove and return element at index 2
print(removed_element)  # 3
print(my_list)  # [1, 2, 4, 5]

last_element = my_list.pop()  # Remove and return the last element
print(last_element)  # 5
print(my_list)  # [1, 2, 4]

# Python program to reverse a linked list
# Time Complexity : O(n)
# Space Complexity : O(n) as 'next'
#variable is getting created in each loop.

# Node class


class Node:

	# Constructor to initialize the node object
	def __init__(self, data):
		self.data = data
		self.next = None


class LinkedList:

	# Function to initialize head
	def __init__(self):
		self.head = None

	# Function to reverse the linked list
	def reverse(self):
		prev = None
		current = self.head
		while(current is not None):
			next = current.next
			current.next = prev
			prev = current
			current = next
		self.head = prev

	# Function to insert a new node at the beginning
	def push(self, new_data):
		new_node = Node(new_data)
		new_node.next = self.head
		self.head = new_node

	# Utility function to print the linked LinkedList
	def printList(self):
		temp = self.head
		while(temp):
			print temp.data,
			temp = temp.next


# Driver program to test above functions
llist = LinkedList()
llist.push(20)
llist.push(4)
llist.push(15)
llist.push(85)

print "Given Linked List"
llist.printList()
llist.reverse()
print "\nReversed Linked List"
llist.printList()