Part 41: The Annoying Guest

Erika had been politely entertained, and it was decided that she would be treated as a guest until the typhoon passed. In the dining hall, Gohda's wonderful dinner had ended, and everyone was relaxing and enjoying some after-dinner coffee and cheese... Apparently, Battler was a bit relieved that Erika had come and turned into a good scapegoat. It drove away some of the attention he'd been getting piled on him for finally coming back after six years.



BGM: Smile-less Soiree

When the conversation turned to a sophisticated discussion of the mystery genre, even the adults were drawn in. She was apparently so well versed that even Nanjo, who had a vast knowledge of the subject, was impressed.



"Have no fear. No matter how difficult the crime, I will solve it. That's a detective's job."
"How reassuring. It almost sounds as though you want a bizarre crime to occur. I hope I don't have to play the part of the victim."
"Dear, don't be imprudent."
"Well, the history of the human mystery genre is only about a century old. Its tricks and ideas are limited to a few recycled patterns, so there's nothing left to show. No matter what kind of impossible crimes or closed room murders might occur, it'll be nothing more than one of the same classes of tricks dressed up to look like something new."
"...The only reason mysteries still make for popular books today is because self-proclaimed 'fans' -- those who work off pieced-together knowledge and who have hardly read any of the classics -- Mistakenly think that a classic trick they didn't know about, through lack of proper study, is actually something new and surprising."

Everyone couldn't help but gape at this imposing claim... If an aged critic had said it, that would have been one thing. But to think that a young person like this could say it so boldly...

"Mystery is a genre that ended a half century ago. At least as far as I'm concerned. However, thanks to the countless ignorant fools, I get to play my part as detective. *giggle* *giggle* *giggle* *giggle*...!"
"By that argument, wouldn't it mean that romance was perfected back in Shakespeare's time, so everything after that isn't worth reading?"
"Exactly. So, if you just read Romeo and Juliet, it's the same as having understood all of romance."
"That's ridiculous. It's not like there's any need to read more books than everyone else just for its own sake, but on the other hand, you can't be so satisfied with just a few stories like that."
"...Just reading classics of the past and never anything new is being overly nostalgic, don't you think? That sounds to me like the excuse of an old person who's too lazy to read anything."
"...That's right. I don't read as much as you, so I get the feeling you'd beat me in an argument."
"Me? Haha, I don't read books."
"..."

Battler chuckled, but Erika knew from the previous game that 'Battler' was actually quite an avid reader. So, his words felt like more of a challenge.



BGM: The Great Detective Knows

"Oh, right. Maria, didn't you bring a quiz book or something?"
"Uu-! Brought it!!"

Picking up that Erika's arrogant statement had made the atmosphere a little more tense, George smoothly changed the subject. By now, it was more than clear that she wasn't the cute guest she had appeared to be. Maria pulled a book out of her bag that had quizzes and puzzles written on it and started reading them to everyone. It might have looked as though it would become a peaceful quiz party... but of course, that isn't what happened.

In credit to all her big talking, Erika managed an impressive ratio of correct and immediate answers... Erika took complete control. Her bragging began to escalate more and more. George slightly regretted the choice he had made when changing the subject.



The question, how many matches would you need for a tournament with 107 teams, was answered instantly by Erika.

"This is less of a puzzle than it is a test of knowledge. There's a formula which shows that the number of matches is always the number of teams minus one. Well, if you just look at the examples showing three matches for four teams and seven matches for eight teams, it should be easy to figure out the pattern."
"Uu-! Erika, that's awesome!"
"Erika onee-chan, right?! Say it."
"Uu-, Erika onee-chan, that's awesome."
"Really impressive. So, you don't call yourself a detective for nothing."
"I couldn't very well act the part of the detective if I was incapable of handling puzzles of this sort."
"Incredible. I'm sure you'll be able to become a real detective in the future."
"Well, I'm pretty sure I already am one."

The cousins all thought about the answers to the questions, but Erika always answered first. Rosa thought that it was a bit rude for Erika to say the answers out loud while people were thinking, instead of keeping them to herself, but since Erika was a guest, Rosa decided against mentioning it. In truth, Erika was perfectly aware of this when she answered the questions instantly. Each time, she would grin broadly, as though saying 'you all still haven't solved such an easy problem?'...

"...Since you're a great detective, you don't really need to take this so seriously, right?"
"Good point. Even though these are just childish questions, I've been taking them a bit too seriously. I'll take more care, so let's hear the next question please."
"Alright, I won't lose this time. Maria, next question please!"



BGM: Scar Sound

"Oh, I know this one. So I guess I'll stay quiet this time."

George, acting like the adult he was, set up a mood that would prevent people from answering right away even if they knew the answer, in effect sending a warning to Erika. It seemed that Erika understood, and she averted her gaze, snorting derisively.

"...To make eight pieces, four slices would be enough, right?"
"That's dumb. It would hardly be a puzzle if that was the answer."
"Hahaha. That's right. These are usually set up so that a smaller number than you'd expect is the answer. But still, how exactly could it be done?"
"...Oh, got it, got it. You can only do this because it's cheese."
"True. If you tried to do it with a birthday cake, there'd be a huge fight."
"Wahahaha! That's right. You might be able to do this with cheese, but you'd never cut a cake like this."
"Huh? Huh? All of you know the answer?! Dammit, am I the only one who doesn't?!"
"Oh, I've got it! I see, so you have to think three-dimensionally."
"Wait, even Jessica?! I don't get it! What should I dooooooo?!"
"Kihihihihihi, I know the answer. It's written right here. Kihihihihi."
"You didn't know the answer until you looked, right?"
"*giggle*, get it? Battler-kun?"
"I see, I understand it as well. This is something you can do because it is cheese."
"Gyah?! Even Doctor Nanjo gets it?! Could it be? Am I the only one who doesn't get it?!"
"...If we tried cooking your brain a bit, it'd probably become as flexible as cheese. *giggle*giggle*..."
"It isn't something like 'use zero slices with the knife and break it apart with your hands', right?"
"Of course not. It's impossible to cut this cheese with anything other than a knife."
"Think of the cheese in three dimensions. If that's hard, it might help to draw a picture on a paper napkin."
"S, so, we have one large piece of cheese, right...? Then we use a knife to make eight pieces... Can the knife only cut in a straight line?"
"Yes, that's right. The knife only cuts in straight lines. Oh, but here's a hint. You can only cut in a straight line, but you're free to cut it wherever you want."
"Try thinking of various ways to stick the knife in."
"You should probably try to think out of the box a bit. Show us what you've got, Battler-kun."

You have a large piece of cheese. How many times must you cut it with a knife to make eight pieces? It's obvious that you could do it in four cuts. Can it be done in even fewer cuts than that? The hints said that it was something that could be done because it was cheese. If it was a birthday cake, you really wouldn't be allowed to do this.



BGM: Melody (instrumental)

"Seems like you've finally hit on it. Hopefully it is the right answer."
"It's impossible to cut the cheese with anything except the knife, right? The knife can only cut in a straight line, right? There aren't any other rules, right? Right?!"
"Uu-. Not really."
"Alright, then that's got to be it! Wheeew, that was a tough one... it's almost like a riddle!"
"Hahahaha, it's just that you won't get anywhere if you always cut down from the top. You make two cuts from the top to get four pieces. If you keep it like that and cut across the side, splitting it into an upper half and a lower half, you get four times two equals eight pieces!"
"It's an answer you can't reach unless you think three-dimensionally. In other words, the correct answer is three."



BGM: Smile-less Soiree

"Wahahahaha! What kind of magic did you use?! There's no way in the world you could manage it with one."
"*giggle*. This isn't a riddle, it's just a normal math problem."
"...Huh? Oh, really...? Nnnnn, I thought of the three-cut method right away, but I figured that was too easy, so I guess I tried to twist it too far..."
"...Battler's answer is smaller than the one in the book. Is Battler right?"



Battler was happy that someone had confirmed his answer. However, at some point, Erika's face had lost its cheeriness.

"...To think that a human other than myself would answer one... and that it'd be you, of all people."
"Your answer was one too, Erika? I guess you were also thinking out of the box."
"It would be truly foolish to arbitrarily decide the shape just because you heard it was a piece of cheese."



"How foolish, child of man. *giggle*giggle*... It says to cut it into eight pieces, but nowhere does it say that they have to be of equal size..."
"It's still impossible. Do you cut it with something other than a knife?"
"The rules say that only the knife can cut it, and that the knife can only cut in a straight line. However, to turn it around, the rules do not say anything besides that... In fact, the shape of the cheese is never specified."



"...I was thinking about sliced cheese, like the kind you might put on your toast for breakfast. After all, I don't usually have anything to do with full blocks of cheese that you'd cut with a knife."
"...The shape of the cheese isn't specified in the rules. A mistake by the ones who made the book. I imagine that there's a picture of a flat cylinder of cheese there in Maria-san's book."
"Uu-. There is. Right here."

As Erika had guessed, the book Maria held had an illustration of a piece of cheese just as Erika had described it. With cheese of this shape, three slices really would be the correct answer. You cut it in a + pattern from the top to make four pieces. Then cut it from the side to double that and make eight pieces. However, since this illustration hadn't been shown, the interpretation of the cheese had been left to the answerer.

"...That is right. When the problem was stated, it never said anything about what the cheese's shape was or how flexible it was."
"Exactly. It seems that Battler-san was the more flexible one, when it comes to both brains and cheese."
"I, I don't get it. How does making it sliced cheese let you cut it into eight parts with a single knife slice?"
"Why not try it with that paper napkin. Pretend it's sliced cheese."
"...It's like this. You fold it accordion-style. How many times do you need to fold it to make eight sections...?"
"Six times."



Once you've done this six times, it looks like the side of an accordion.

"With normal cheese, it'd break if you tried to fold it like this, but the rules say that this cheese can't break unless you use a knife, right...?"
"Yes, no problems there. After all, this is magic cheese that can only be cut by the knife."
"After folding it, if you start at the top and make a cut right down the middle..."



"W, wait a second. The parts aren't all equal this way, right...?!"
"...All the questioner said was to cut it into eight pieces. They didn't say anything about them being equal."
"...Well, if you change the way you fold it, it is possible to make them all equal sizes, but I wouldn't want to confuse you stiff-headed people with the explanation. Eheheheheheheheheheh..."
"Oh, ooooooohhh..."

For a while, everyone was stunned... Battler had reached a far better answer than three by thinking of the problem as a riddle. Erika had already known both answers and had even spotted a mistake made by the book. The others could do nothing but stare at those two in surprise.

"I, incredible. So we were the stiff-headed ones...?"
"What... a failure."
"We were thinking in three dimensions, but it looks like Battler-kun and Erika-chan were thinking in one dimension higher."



BGM: FIshy Aroma

"What are you talking about...? Is that a quote from some novel...?"
"...Well, let's call it that for now, shall we? Anyway, I guess this means that everyone's brains are as stiff as rock-hard cheese. *giggle*giggle*giggle*...!"

Without any signs of restraint, Erika looked at everyone and laughed sarcastically... Only Maria didn't notice the venom in that laugh as she happily turned to the next page.







"Here's another cliched problem. Don't tell me that you'll all need to waste several precious seconds on a problem like this...?"

By now, Erika was gazing around with an unpleasant look, acting in a manner that was completely inappropriate both for a guest and for someone of her age... She was no longer a guest who would be staying until the storm passed. She had transformed into an annoying guest who wouldn't leave until the storm passed... Everyone thought this, but they were unable to say it aloud...

"Uh, oh, right, speaking of problems with coins, I've heard that you can tell whether someone's good with chopsticks or not by seeing if they can pick up coins with them..."



BGM: HANE

Jessica was about to say 'isn't a chopstick just a stick?'...but stopped herself just in time. She realized that it was best to let George take control for now...

"I have a coin here, so would you like to challenge me? I'm pretty good with chopsticks."
"Th, that's right... We trained George very well with chopsticks."
"True. Upbringing is what makes for good table manners. Erika-san was very impressive herself."
"I'll lend you some coins too. It'll probably be more fun with more of them."
"Jessica. Watch closely and learn."
"D, dammit...!"
"Alright, let's go. Let's see who can move the most coins over to their plate."
"Bring it on!! Chopsticks, chopsticks, haah haah!!"

...This time, George had steered the conversation into a good direction. Everyone else understood, and they helped to egg on this chopstick fight and change the subject. They were fully aware by now that Erika was extremely proud of her intelligence. And apparently, she had the bad habit of using that to look down on other people.