# lowercase_word_cipher.py
# encode a word by shifting the letters along the alphabet
#
word = raw_input("What is the word to encode? (lowercase a-z only) ")
cipher_key = input("What is the secret key? (-25 to 25) ")
code_word = ""                                  # initialze accumulator
for letter in word:
  char_number = ord(letter) - ord('a')          # number is from 0 to 26
  code_number = (char_number + cipher_key) % 26 # shift, wrapping around at 'z'
  code_letter = chr(code_number + ord('a'))     # convert back to a letter
  code_word = code_word + code_letter           # grow answer in accumulator
print "The coded word is '{}'.".format(code_word)