s = input()
change_list = []
for i in range(len(s)):
    change_list.append(i)

answer_list = []

s_idx = 0
for c in s:
    real_change = (change_list[s_idx]+1) % 26

    if ord(c) - real_change < ord('A'):
        answer_list.append(chr(ord('Z') +1 - (ord('A') - (ord(c) - real_change))))
    else:
        answer_list.append(chr(ord(c) - real_change))
    s_idx += 1

res = ''.join(answer_list)
print(res)