import sys
read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines

S = [int(x) - ord('A') for x in read().rstrip()]

T = [(x - i) % 26 for i,x in enumerate(S,1)]
answer = ''.join(chr(x + ord('A')) for x in T)
print(answer)