def ackermann(m, n):
    stack = []
    stack.append(m)
    while stack:
        m = stack.pop()
        if m == 0:
            n = n + 1
        elif n == 0:
            n = 1
            stack.append(m-1)
        else:
            n = n - 1
            stack.append(m-1)
            stack.append(m)
    return n

ackermann(int(input()), int(input()))