# -*- coding:utf-8 -*-

if __name__ == "__main__":
	s = list(raw_input())
	al = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
	al = list(al)
	for i in xrange(len(s)):
		num = al.index(s[i])
		num -= (i+1) % 26
		if num < 0:
			num += 26
		s[i] = al[num]
	print ''.join(s)