You have two integers $l$ and $r$. Find an integer $x$ which satisfies the conditions below:

• $l \le x \le r$.
• All digits of $x$ are different.

If there are multiple answers, print any of them.

Input

The first line contains two integers $l$ and $r$ ($1 \le l \le r \le 10^{5}$).

Output

If an answer exists, print any of them. Otherwise, print $-1$.

见题面 Input 部分

见题面 Output 部分

In the first example, $123$ is one of the possible answers. However, $121$ can't be the answer, because there are multiple $1$s on different digits.

In the second example, there is no valid answer.