ms@fp

23rd Birthday

Michal, soon aged 23, is thinking of having a birthday party with his friends. He typically likes to follow a schedule which consists of Physical and Mental activities. In particular, he enjoys Working out (P), Hiking (P), Reading books (M), and learning a new Language (L). However, Michal is unsure what schedule he should make for the 28-th, his birthday, since he wants to see this friends at 18:00, so he’s limited to a 12-hour schedule this time (he typically has an alarm set to 6AM).

Fortunately or not, he struggles to focus on one activity at a time. He thereby usually switches from an activity to another every 30 minutes. However, he ain’t no robot! If he is focused for 2 hours straight (he can never do 5 activities in a row), he needs to take a break (also 30 minutes) immediately afterwards.

At the end of the day, he creates a table and assigns a score (based on the enjoyment gained) to each activity. In his opinion, reading books is the coolest, so he assigns a +3 to it. He also enjoys sports, so either physical activity makes up for a +2. Lastly, while learning a new language is rewarding, it’s also difficult; +1 for the last one. However, Michal has noticed that if he takes on a physical activity and then studies a language right afterwards, he can focus better, so it isn’t as difficult as it usually tends to be, and he enjoys it much more! Then he receives +2 extra scores. Lastly, since Michal is motivated, he wants to minimize his breaks, so he receives 0 for each.

He recently read in an article that randomization isn’t too bad*. He decided to write a QuickCheck generator that would create a schedule for him: a sequence of 24 physical/ mental activities. But he wasn’t much satisfied—the tool didn’t generate any breaks in between for him—so he’s unsure when he shall rest (instead of doing some of the activities). Because he’s still new to QuickCheck, he couldn’t fix the error, so he left the generator unchanged, and decided to go with it.

Now Michal needs your help!


(the template can be obtained here)

Example

Input

WL

Output

5

That is, \(2 + 1 + 2\) (bonus applied).

Input

RRLRR

Output

12

He rests instead of learning a language (L), so the sequence becomes RRBRR, so he receives 3 for each R. He has rested enough.

Input

WWWWL

Output

9

He wants to boost his language learning, so he decides to work out, then study Italian afterwards, the sequence becomes e.g. WWBWL. Then he receives \(2*2 + 2 + 1 + 2\), where the last \(2\) is the bonus which he didn’t want to miss.

[*]: https://pickowheel.com/blog/posts/the-psychology-of-randomness