root = input()
d, num = 0, 1

for _ 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:]
    d += 1

print(num)