Problem9715--ABC192 —— C - Kaprekar Number

9715: ABC192 —— C - Kaprekar Number

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Time Limit : 1.000 sec  Memory Limit : 512 MiB

Description

For an integer $x$ not less than $0$, we define $g_1(x), g_2(x), f(x)$ as follows:

-   $g_1(x)=$ the integer obtained by rearranging the digits in the decimal notation of $x$ in descending order
-   $g_2(x)=$ the integer obtained by rearranging the digits in the decimal notation of $x$ in ascending order
-   $f(x)=g_1(x)-g_2(x)$

For example, we have $g_1(314)=431$, $g_2(3021)=123$, $f(271)=721-127=594$. Note that the leading zeros are ignored.

Given integers $N, K$, find $a_K$ in the sequence defined by $a_0=N$, $a_{i+1}=f(a_i)\ (i\geq 0)$.

Input

Input is given from Standard Input in the following format:

```
$N$ $K$
```

Output

Print $a_K$.

Constraints

-   $0 \leq N \leq 10^9$
-   $0 \leq K \leq 10^5$
-   All values in input are integers.

Sample 1 Input

314 2

Sample 1 Output

693

We have:

  • $a_0=314$
  • $a_1=f(314)=431−134=297$
  • $a_2=f(297)=972−279=693$

Sample 2 Input

1000000000 100

Sample 2 Output

0

We have:

  • $a_0=1000000000$
  • $a_1=f(1000000000)=1000000000−1=999999999$
  • $a_2=f(999999999)=999999999−999999999=0$
  • $a_3=f(0)=0−0=0$

Sample 3 Input

6174 100000

Sample 3 Output

6174

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