2016/quals/text_editor.md

You have a list of **N** distinct words, consisting of only lowercase letters.
You'd like to print any **K** words from this list, one per page, in any
order.

You will accomplish this using a very basic text editor. It supports 3 types
of operations: typing a letter, deleting the previous letter, and printing the
current document. Note that it does not allow the cursor to be moved! This
means that the first operation may only add a letter to the end of the
document, and the second may only delete the last letter (if any). Due to
issues with memory leakage, you also need to remember to leave the document
completely empty after you've printed your **K** words!

What's the minimum number of operations required to get the job done?

As an example, let's say that you want to print 3 of the following 5 words:

    a
    hair
    box
    awesome
    hail

One optimal sequence of 15 operations is as follows:

  * \- type 'h', 'a', 'i', and 'r' (document = 'hair') 
  * \- print 
  * \- backspace (document = 'hai') 
  * \- type 'l' (document = 'hail') 
  * \- print 
  * \- backspace 4 times (document = empty) 
  * \- type 'a' (document = 'a') 
  * \- print 
  * \- backspace (document = empty) 

### Input

Input begins with an integer **T**, the number of sets of words you want to
print. For each set, there is first a line containing the space-separated
integers **N** and **K**. The next **N** lines contain the set of words, one
per line.

### Output

For the **i**th set of words, print a line containing "Case #**i**: " followed
by the minimum number of operations required to print **K** of the words and
then leave the document empty.

### Constraints

1 ≤ **T** ≤ 100  
1 ≤ **K** ≤ **N** ≤ 300  
The total length of all **N** words in each set will be at most 100,000
characters.