from string import ascii_lowercase as lower





def main():

    C = eval(input())

    for i in range(28):

        if C == lower[i]:

            print((lower[i+1]))

            break





if __name__ == '__main__':

    main()
def main():

    c = eval(input())

    print((chr(ord(c) + 1)))





if __name__ == '__main__':

    main()



from string import ascii_lowercase as lower


def main():
    C = eval(input())
    for i in range(28):
        if C == lower[i]:
            print((lower[i + 1]))
            break


if __name__ == "__main__":
    main()

def main():
    c = eval(input())
    print((chr(ord(c) + 1)))


if __name__ == "__main__":
    main()

-from string import ascii_lowercase as lower - - -    C = eval(input()) -    for i in range(28): -        if C == lower[i]: -            print((lower[i + 1])) -            break +    c = eval(input()) +    print((chr(ord(c) + 1)))