N, K = map(int, input().split())

left_end = K - 1
right_end = N
cnt = N - 1
ans = K  # This will be overwritten except when N=1

while cnt > 0:
    L = left_end
    R = right_end - K  # right_end - (K + 1) + 1 = right_end - K
    
    if L > R:
        max_steps = L - R
        t = min(max_steps, cnt)
        ans = left_end - t + 1
        left_end -= t
        cnt -= t
    elif R > L:
        max_steps = R - L
        t = min(max_steps, cnt)
        ans = right_end - t + 1
        right_end -= t
        cnt -= t
    else:
        # L == R, choose left
        ans = left_end
        left_end -= 1
        cnt -= 1

print(ans)