Problem10904--ABC361 - C - Make Them Narrow

10904: ABC361 - C - Make Them Narrow

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Time Limit : 1.000 sec  Memory Limit : 512 MiB

Description

You are given a sequence $A$ of length $N$.  
Freely choose exactly $K$ elements from $A$ and remove them, then concatenate the remaining elements in their original order to form a new sequence $B$.  
Find the minimum possible value of this: the maximum value of $B$ minus the minimum value of $B$.

Input

The input is given from Standard Input in the following format:

```
$N$ $K$
$A_1$ $A_2$ $\dots$ $A_N$
```

Output

Print the answer as an integer.

Constraints

-   All inputs are integers.
-   $1 \le K < N \le 2 \times 10^5$
-   $1 \le A_i \le 10^9$

Sample 1 Input

5 2
3 1 5 4 9

Sample 1 Output

2

Consider removing exactly two elements from $A=(3,1,5,4,9)$.

  • For example, if you remove the 2nd element $1$ and the 5th element $9$, the resulting sequence is $B=(3,5,4)$.
    • In this case, the maximum value of $B$ is $5$ and the minimum value is $3$, so (maximum value of $B$) $-$ (minimum value of $B$) $=2$, which is the minimum possible value.

Sample 2 Input

6 5
1 1 1 1 1 1

Sample 2 Output

0

Sample 3 Input

8 3
31 43 26 6 18 36 22 13

Sample 3 Output

18

Source/Category