import string

alphabets = string.ascii_uppercase
cryptgraphy = list(input())

def num_to_alphabet(num):
  alphabet_index = num % 26
  return alphabets[alphabet_index]

def alphabet_to_num(alp):
  return alphabets.index(alp)

unraveled_cryptgraphy = []
number = 0
for i in cryptgraphy:
  new_num = alphabet_to_num(i)
  number += 1
  unraveled_cryptgraphy.append(num_to_alphabet(new_num - number))

print(''.join(unraveled_cryptgraphy))