root = input()
num =  1

for d in range(len(root)):

    if root[0] == "L":
        num = (2 **(d + 1) - 1) + (num - 2**d) * 2 + 1
    else:
        num = (2 **(d + 1) - 1) + (num - 2**d) * 2 + 2

    root = root[1:]

print(num)