def main():
    inp = input()
    temp = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"

    count = 1
    ans = ""
    for s in inp:
        ans = ans + temp[temp.index(s) - count % len(temp)]
        count += 1
    print(ans)
    
    
if __name__ == '__main__':
    main()