| This morning you woke up with an uncontrollable urge to send a text message |
| made up of **K** distinct words. But, can you believe it? Your new phone just |
| crashed and all of the words are missing from its dictionary! You used to have |
| **N** words in there, and you certainly don't have time to add all of them |
| back right now. |
|
|
| Your plan is to just choose **K** of the **N** possible words, add them to |
| your phone's dictionary, and then text each of them. To text a certain word, |
| you must either type the word itself, or any nonempty prefix of it which is |
| not a prefix of any other word in the dictionary. |
|
|
| What's the minimum number of letters you must type to send your message of |
| **K** words? |
|
|
| ### Input |
|
|
| Input begins with an integer **T**, the number of test cases. For each test |
| case, there is first a line containing the space-separated integers **N** and |
| **K**. Then, **N** lines follow, each containing a word that used to be in |
| your phone's dictionary. |
|
|
| ### Output |
|
|
| For the **i**th test case, print a line containing "Case #**i**: " followed by |
| the minimum number of characters you need to type to send your text message. |
|
|
| ### Constraints |
|
|
| 1 ≤ **T** ≤ 20 |
| 2 ≤ **N** ≤ 4,000 |
| 1 ≤ **K** ≤ min(**N**-1, 100) |
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|
| The **N** words will have a total length of no more than 20,000 characters. |
| The words are made up of only lower-case alphabetic characters. |
| The words are pairwise distinct. |
|
|
| ### Explanation of Sample |
|
|
| In the first case, one option is to choose the words "tin", "tinny", |
| "gigantic", and "tilts". You can then text these words by typing "tin", |
| "tinn", "g", and "til", respectively, for a total of 3+4+1+3=11 letters. |
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