Caesar Cipher

In cryptography, a Caesar cipher is one of the simplest and most widely known encryption techniques. It is a type of substitution cipher in which each letter in the plaintext is replaced by a letter some fixed number of positions down the alphabet. For example, with a right shift of 3, A would be replaced by D, B would become E, and so on. The method is named after Julius Caesar, who used it in his private correspondence

The following python program shows how the Caesar cipher works.

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def encrypt(text,s):
   result = ""

   # transverse the plain text
   for i in range(len(text)):
      char = text[i]

      if (char.isupper()):
         result += chr((ord(char) + s - 65) % 26 + 65)
      else:
         result += chr((ord(char) + s - 97) % 26 + 97)

   return result

text = "I am an awesome cskitty"
s = 4

print "Plain Text : ", text
print "Shift pattern : ",str(s)
print "Cipher: " + encrypt(text,s)

Question: can you design a decryption function?