def gen(N):
    # 1,1,1,1..
    yield N - 1, N

    # 1, -1, 1, -1, ...
    s = N // 2
    t = N - s
    yield -(N - 1), s - t
    yield -(N - 1), t - s

    # -1, -1, ...
    yield N - 1, -N


N, A, B = map(int, input().split())

print(min(A * x - B * y for x, y in gen(N)))