# -*- coding: utf-8 -*-
R ="ABCDEFGHIJKLMNOPQRSTUVWXYZ"
Rlist = list(R)
S = raw_input()
Slist = list(S)
for i in range(0, len(Slist)):
    no = Rlist.index(Slist[i])
    no = (no - i - 1) % 26
    Slist[i] = Rlist[no]
print "".join(Slist)