def conversion(a, b):
    c = ord(a)
    d = c - b
    return (chr(kaiki(d)))

def kaiki(a):
    if a >= 65:
        return a
    else:
        a += 26
        kaiki(a)

inp = input()
out = ""
for i in range(len(inp)):
    x = i + 1
    returns = conversion(inp[i], x)
    out += returns
print(out)