viruses which are in capsules numbered from to , however not all capsules have a virus in them. has an extermination ray that can exterminate capsules in the range (This includes ones that contain virus and ones that do not). However, he can only use the ray **up to** times.

Since capsules are quite expensive, can you tell

what is the total minimum number of capsules that he has to destroy to exterminate the virus?#### Input Specification

First line, 3 integers , , , denoting the number of capsules, maximum number of times can use the ray, and the number of viruses respectively.

Next lines, the capsule number , denoting where the virus resides in .

#### Output Specification

Output one integer, the minimum number of capsules that needs to be destroyed in order to exterminate the virus.

#### Subtasks

For all subtasks:

##### Subtask 1 [30%]

##### Subtask 2 [70%]

No further constraints.

#### Sample Input

```
10 2 5
3
4
5
7
10
```

#### Sample Output

`6`

#### Sample Explanation

and then on capsule , which will result in total capsules destroyed, including the capsules that did not have the virus in them.

can use the ray on capsules
## Comments