Countdown to PDC09: Office, SharePoint, Free Win7 Boot Camp, and Turtles

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Developers scoffing at Office and SharePoint?  Not anymore they don’t!  Steve Fox, the productivity track owner for Office, SharePoint, CRM and Unified Communications, talks to us about what kind of IW dev content we’ll have on these technologies at PDC, and what to expect that is different from the other events featuring these same products.  We also announce the FREE Windows 7 Developer Boot Camp that will be held on November 16 at PDC, and Mike gives another hint to the last Hard Hat Challenge which remains unsolved: turtle! 


PDC09, PDC 2009



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The Discussion

  • User profile image
    Michael Price

    Hmmm.  When you said Logo before, turtle was what I was thinking.

  • User profile image

    I was sent the image with no description for a friend. Took a while to find this place via random google searches. That was as much of a puzzle as the challange. I think they are trying to win the shirt without telling me! I follow the clues. I was about to post in the last blog post if "Green" would be a valid clue. Turtles are green. I've been fooling with it for a few minutes pen and paper style. I sure could use a new shirt Smiley


    EDIT: drink your ovaltine??!!! C'MON! This turtle must be teen-aged and mutant cause I'm getting my butt kicked!

  • User profile image

    This hardhat challenge with those weird annonations about Ralphie from the Ninja Turtles freaks me out! Wait a second... wasn't that the computer guy? Was he using LOGO? I don't get it, and I probably don't care about a T-shirt that much... Wink

  • User profile image

    And the turtle knew a few simple rules. I still can't figure out the encoding though... I've got him doing things based on the dots but nothing that looks like anything. I thought it would be fairly obvious given the clues and the data. It's not so obvious. Obviously.

  • User profile image

    My first session got me pretty far. You can clearly see the PDC 09 logo, although it's not 100% correctly traced, probably due to the instruction set

  • User profile image

    Congratulations, exoteric! While the instruction set might not be perfect, you did provide the correct answer. So that we can track the solution in this thread, will you briefly explain your solution here? Also, drop an e-mail to pdc09 (at) so we can coordinate the t-shirt.


    And special thanks to Adam for submitting this Hard Hat Challenge. Looks like it's time for a new puzzle. Smiley

  • User profile image

    Let's see.


    Analysis: It was obvious from the outset that this was probably a binary sequence or at least could be seen as one. Then the question was what domain did it represent, and ultimately what object. This quickly turned out to be turtle graphics (familar since basic school and much more recently with L-systems, personally speaking). Then in what order to read the bits (top-left to bottom-right; reverse; diagonal, etc. ). Then how to cluster the bits. The latest clues provided the obvious answer. Then the question was what the concrete instruction set to map the bit pairs to. There are many possible instruction sets and many permutations. So first I tried a couple of permutations manually, then set out to do so more systematically by simply querying for all permutations and switching through them.


    Implementation: The first ideas was: do not simply provide a final answer, rather show the steps. So I thought I needed to have n steps where each step is represented as an image. C# 2.0 lazy iteraters are perfect for possibly infinite and lazy lists. This was used to set up a pipeline of solutions or steps. Every solution is an image and the enumerator holds the current state of the pipeline where the button simply pushes the computation ahead until exhausted. The code is available in the thread I linked to.


    The code is very hacky and does not deal correctly with disposables, but it's just a quick hack after all. The final solution was not nailed, but was enough to tell the text.


    E-mail on the way.


    See also -

  • User profile image

    Congratulations exoteric, I think you would have eventually get the correct instructions.


    The correct Logo Instruction Set is;-


    00 Rotate Clockwise 45

    01 Pen Down

    10 Pen Up

    11 Move Forward


    I also used simplified transformations for the angle, which one of the reasons why your drawing didn't align correctly.

    The "turtle" started heading North (0 Degrees)


    Angle  DX DY
    0      +0 -1
    45     +1 -1
    90     +1 +0
    135    +1 +1
    180    +0 +1
    225    -1 +1
    270    -1 -0
    315    -1 -1

    Edit:  Pen Down & Pen Up Corrected thanks to FollowingSky. Well Spotted (I didn't spot that one.)

  • User profile image

    Ya I was much closer than i thought. I started with left 90 right 90 forward 10 back 10 with permutations of the bits. When that didn't work i wrote 4 functions that would make the turtle go up 10 down 10 right 10 and left 10. No permutation of those worked out either. Never considered checking for pen up and pen down.


    Here's 10 seconds more work with the correct instructions...



    My pen up and pen down is off. I think the instructions are flipped above.... anyway cool deal to see it work out Smiley I look forward to the next one.

  • User profile image

    Bah, I was quite close, I even tried up/down at some point. Thanks for the challenge, Adam Smiley

  • User profile image

    Your correct about the Pen Down & Pen Up being flipped. Thank You. Embarassed

    I've editted the post to include the correction.


    Added the code I used to draw the graphics to the challenge thread.

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