Let us define $\mathrm{mex}(x_1, x_2, x_3, \dots, x_k)$ as the smallest non-negative integer that does not occur in $x_1, x_2, x_3, \dots, x_k$.  
You are given an integer sequence of length $N$: $A = (A_1, A_2, A_3, \dots, A_N)$.  
For each integer $i$ such that $0 \le i \le N - M$, we compute $\mathrm{mex}(A_{i + 1}, A_{i + 2}, A_{i + 3}, \dots, A_{i + M})$. Find the minimum among the results of these $N - M + 1$ computations.

Input is given from Standard Input in the following format:

```
$N$ $M$
$A_1$ $A_2$ $A_3$ $\dots$ $A_N$
```

Print the answer.

-   $1 \le M \le N \le 1.5 \times 10^6$
-   $0 \le A_i \lt N$
-   All values in input are integers.

1

We have:

• for i=0: mex($A_{i+1},A_{i+2}$)=mex(0,0)=1
• for i=1: mex($A_{i+1},A_{i+2}$)=mex(0,1)=2

Thus, the answer is the minimum among 1 and 2, which is 1.

0

We have:

• for i=0: mex($A_{i+1},A_{i+2}$)=mex(1,1)=0
• for i=1: mex($A_{i+1},A_{i+2}$)=mex(1,1)=0

2

We have:

• for i=0: mex($A_{i+1},A_{i+2}$)=mex(0,1)=2
• for i=1: mex($A_{i+1},A_{i+2}$)=mex(1,0)=2