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