inp = list(input())
n = len(inp)

aset = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"

seq = []
alp = []
for i in range(n):
    seq.append(i)
    alp.append(aset.find(inp[i]))

ans = []
for i in range(n):
    if i > 26:
        i = i%26
        conv = aset[alp[i]-seq[i]-1]
        ans.append(conv)
    else:
        conv = aset[alp[i]-seq[i]-1]
        ans.append(conv)
print("".join(ans))