import sys
read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines
sys.setrecursionlimit(10 ** 7)

s = readline().rstrip().decode()
al = [chr(ord('A') + i) for i in range(26)]
ans = ''
for i in range(len(s)):
    index = (al.index(s[i]) - i - 1) % 26
    ans += al[index]
print(ans)