def main():
    S = input()
    now, L, R = 1, 2, 3
    for s in S:
        if s == "L":
            now, L, R = now * 2, L * 2, R * 2 + 1
        else:
            now, L, R = now * 2 + 1, L * 2, R * 2 + 1
    print(now)

if __name__ == "__main__":
    main()