Password

Limits: 2 sec., 256 MiB

Zenyk wants to know the password to Marichka’s Facebook account.

There are $n$ digits (1 to 9) lying on the floor. Zenyk knows that he should form $k$ integers using those digits, in such a way the greatest integer is minimum possible — that would be the password. Of course, you have to use all $n$ digits.

Please help Zenyk to find out the password.

Input

The first line contains two integers $n$ and $k$. The second line contains string of $n$ digits 1 to 9.

Output

Print a single integer — the password.

Constraints

$1 \le N \le 10^5$,

$1 \le K \le N$.

Samples