def main():
    S = input()
    print(get_result(S))

def get_result(string):
    if len(string) == 0:
        return 0

    binary = string.replace('L', '0').replace('R', '1')
    ordinary = int(binary, 2)
    #print(ordinary)

    start = 2 ** len(string)
    #print(start)

    return (start + ordinary)

if __name__ == '__main__':
    main()