#coding: UTF-8

import sys
from math import pi
from collections import deque
from functools import reduce

### defs ###

### main ###
S = sys.stdin.readline().strip('\r\n')
ans = ''
for i in range(len(S)):
	x = ord(S[i])-i-1
	if (x < ord('A')):
		while (x < ord('A')):
			x += 26
	ans += chr(x)
print(ans)