def main():
    import sys
    input = sys.stdin.readline
    S = input()
    chars = {
    "A":1,"B":2,"C":3,"D":4,"E":5,
    "F":6,"G":7,"H":8,"I":9,"J":10,
    "K":11,"L":12,"M":13,"N":14,"O":15,
    "P":16,"Q":17,"R":18,"S":19,"T":20,
    "U":21,"V":22,"W":23,"X":24,"Y":25,
    "Z":26}
    alpha = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"

    s = ""
    for i in range(len(S)-1):
        a = S[i]
        n = chars[a] - (i + 1)
        n %= 26
        s += alpha[n-1]
    print(s)
if __name__ == '__main__':
    main()