import sys
import random
import string
import operator

alphabet='ABCDEFGHIJKLMNOPQRSTUVWXYZ'

def caesar_enc(letter):
  if letter < 'A' or letter > 'Z':
    print 'Invalid letter'
    return
  else:
    return alphabet[(ord(letter) - ord('A') + 3) % len(alphabet)]

def caesar_enc_string(plaintext):
    ciphertext = ''
    for letter in plaintext:
        ciphertext = ciphertext + caesar_enc(letter)
    return ciphertext

def main():
  m = 'BINEATIVENIT'
  c = caesar_enc_string(m)
  print c
  

if __name__ == "__main__":
  main()