Wednesday, April 22, 2009

would you get to drive the porsche?

Back in the day, after 9/11, I moved from San Fran to DC to help out this 3 letter collective on a project.

I didn't do a good job of ingratiating myself with the team. They were trying to foist a bunch of bullshit work off on me. I was not having it. Then I stood up in a meeting and told a bunch of contractors they were all terrorists because they were more concerned with how much they would get paid for their work than actually doing their work. I was summarily fired and then before that could actually happen rehired because the head gov guy liked that I did that.

I was put in the architecture group, working for a guy named Barry. Barry looks like yoda, if yoda only weighed 70 lbs. We made sure that, for every award he won, they spelled his name "Berry" on the certificate or plaque. He never noticed.

Barry wanted less than nothing to do with me. So he tried to annoy the ever loving shit out of me every day to get me to quit. I finally decided a detente at the local watering hole was in order.

As we sat there with our beers (back when I could drink beer), Barry asked me if I liked logic puzzles. I had never given them much thought. He gave me a simple puzzle (the old "cannibal which village do you go to") and I solved it pretty quickly. We then moved on to the bags of marbles, candle fuses, etc. Before I knew it, it was really late and Barry was running out of puzzles. I discovered then that I love logic puzzles, and that being good at solving them raised my street cred with Barry.

Next happy hour, Barry told me that he was going to give me a really hard puzzle. It had taken him 4 years to solve. He wondered if I could solve it faster. I countered with an incentive to solving the puzzle faster. I said that if I could solve it in less than 4 years Barry would have to let me drive his Porsche. It was a beauty, fuck me red, 1,500 miles on it, and just screaming for action.

I solved the puzzle in 4 weeks. Barry had to let me drive his car. Barry thought I was going to take a lap around the parking lot with it. Instead I drove it to Annapolis (about 40 miles from our office). I got it up to 120 MPH on a lesser highway in Maryland, in the rain, while Barry kept commenting, in a high pitched voice "Uh, you can see how fast you're going because there's a digital display of the speedometer on the windshield".

So here's the puzzle. I figured out the crux of the question you have to ask within a minute of getting the puzzle, but it took me a while, and many truth tables, to figure out how to formulate the question.

If you want to solve it, you have to do it without cheating and looking the answer up on the net or in a book.

You are in a room with a knight, a liar, and a knave. For those unfamiliar with logic puzzles, a knight always tells the truth, the knave can lie or tell the truth, and the liar always lies. In three questions you have to correctly identify who is who. The puzzle solution is the three questions.

If you solve the puzzle, I will paint a picture of what ever you want me to paint. You've seen my skills at painting. So yeah, it's kind of a shit reward. But, you will get to tell all your friends why you have such a crap painting hanging in your bedroom. Or where ever you put it.

Game on.

5 comments:

  1. I am concerned with anyone that would move from San Fran to DC, well.. for any reason; especially to work for some half witted spook agency full of morons.

    I would like to drink beer with you in spite of this and your weak attempt at a logic puzzle, though I much prefer good wine.

    Try this.

    The Grand Master takes a set of 8 stamps, 4 red and 4 green, known to the logicians, and loosely affixes two to the forehead of each logician so that each logician can see all the other stamps except those 2 in the Grand Master's pocket and the two on her own forehead. He asks them in turn if they know the colors of their own stamps:
    A: "No."
    B: "No."
    C: "No."
    A: "No."
    B: "Yes."
    What color stamps does B have?


    I'll take one of your paintings one day. Keep practicing.

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  2. It wasn't my choice to move. I had to in defense of people like you who leave annoying comments on my blog.
    I don't drink beer.
    If my puzzle is so easy, what's the answer.
    And, I'll have an answer for you.
    You only get a painting if you are a good friend of mine, or if you answer the puzzle.

    ReplyDelete
  3. Let A, B, and C be placeholders/variables for each of the
    creatures


    Ask the knave to raise his hand.

    If ((A=UP) & (B=UP) & (C=DOWN)) then
    C <--- Knight;
    Ask The Knight which of the other two
    is the liar.
    If (Liar = B) then
    A <--- Knave;
    Else /* Liar is A */
    B <--- Knave;
    End If;
    Else
    If ((A = UP) & (B = DOWN) & (C = DOWN)) then
    A <-- Liar;
    Ask Liar which is Knight;
    If Liar says knight is B then
    C <--- Knight;
    B <--- Knave;
    else /* Liar says knight is C */
    B <--- Knight;
    C <--- Knave;
    end if;
    end if;

    ReplyDelete
  4. Interesting solution...except that you can't ask all three a question at the same time. You can only ask each individual a question.

    The first question does have to identify the knave. It's the same kind of question you ask to identify which way leads to the cannibals and which way leads to the village where you won't get eaten.

    ReplyDelete
  5. The answer to the stamp question is B has two stamps of the same color. If B had mixed stamps A should have been able to guess his stamps.

    ReplyDelete