Add files via upload

Author: akshad110

casear_cipher/main.py

@@ -0,0 +1,41 @@
+letters = ['a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z'
+           'A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z'
+          ]
+
+
+def encryption(plain_message,shift_key):
+    ciper_text =""
+    for char in plain_message:
+        if char in letters:
+           position = letters.index(char)
+           new_position = (position+shift_key)%26
+           ciper_text += letters[new_position]
+        else:
+            ciper_text += char
+    print(f"The encrpyted cipher text is: {ciper_text}")
+
+def decryption(cipher_text,shift_key):
+    plain_message =""
+    for char in cipher_text:
+        if char in letters:
+           position = letters.index(char)
+           new_position = (position-shift_key)%26
+           plain_message += letters[new_position]
+        else:
+            plain_message += char
+    print(f"The decrpyted cipher text is: {plain_message}")
+
+flag = False
+while not flag:
+    en_dn = input("Type encrypt for encryption, Type decrypt for decryption: \n")
+    message = input("Enter your Message: \n").lower()
+    shift = int(input("Type shift number: \n"))
+
+    if en_dn == "encrypt":
+        encryption(plain_message=message, shift_key=shift)
+    elif en_dn == "decrypt":
+        decryption(message, shift)
+    play_again = input("Do you want to play again 'yes' or 'no': ")
+    if play_again == 'no':
+        flag = True
+        print("Good bye!!!")