def walk_national_root(root, branch_root):
    courent_root = root
    for i in range(len(branch_root)):
        if branch_root[i] == "L":
            courent_root = courent_root * 2
        elif branch_root[i] == "R":
            courent_root = courent_root * 2 + 1
    return courent_root


def main():
    root = 1
    try:
        branch_root = list(input())
        answer = walk_national_root(root, branch_root)
        print(answer)
    except EOFError as e:
        print(root)


if __name__ == "__main__":
    main()