PROBLEM STATEMENT

There is nothing more beautiful than just an integer number.



You are given an integer n.  Write down n in decimal notation with no leading zeroes, and let M be 
the number of written digits.  Perform the following operation exactly k times:

Choose two different 1-based positions, i and j, such that 1 &lt= i &lt j &lt= M. Swap the digits 
at positions i and j.  This swap must not cause the resulting number to have a leading zero, i.e., 
if the digit at position j is zero, then i must be strictly greater than 1.




Return the maximal possible number you can get at the end of this procedure.  If it's not possible 
to perform k operations, return -1 instead.



DEFINITION
Class:TheSwap
Method:findMax
Parameters:int, int
Returns:int
Method signature:int findMax(int n, int k)


CONSTRAINTS
-n will be between 1 and 1,000,000, inclusive.
-k will be between 1 and 10, inclusive.


EXAMPLES

0)
16375
1

Returns: 76315

The optimal way is to swap 1 and 7.

1)
432
1

Returns: 423

In this case the result is less than the given number.

2)
90
4

Returns: -1

We can't make even a single operation because it would cause the resulting number to have a 
leading zero.

3)
5
2

Returns: -1

Here we can't choose two different positions for an operation.

4)
436659
2

Returns: 966354



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