Friday, February 27, 2009


Life is unfettered as usual. Nothing much to think about, nothing much to do, nothing quite a few respects. Hence the title of the post. Bengali people will catch has to do with certain plain-tasting but healthy vegetables. So is life healthy when it is plain? Studies will show, with definite certainty and a ten-minute warranty that both viewpoints (the statement and its reverse) are absolutely 100% on the spot. So, as a friend of mine so unobtusely observes, WDW!
Slumdog Millionaire has swept the oscars with 8 wins out of 10. Kate Winslet has realized finally that the oscar statuette is actually not a shampoo bottle. Ben Stiller has lost his razor and a few of his marbles. A R Rahman has redefined the word "laconic". So what do we take home from all this? IMO, a cold breakfast and 3 hours of wasted sleep.
Last week's movie had "The Kite Runner" on show. Pretty good movie. Kites, other things featured prominently. A cowardly young boy with a baloonful of hot air "grows up" and rescues his "nephew", both physically and mentally, from the nasty talibani once-neighbourhood-bully. Very nice. Very...cathartic. Two hours was not wasted.
Recently, Hofstadter (hope the spellings wrong) has been talking (to me) about Bach, Escher and Godel. What the poor fellow does not realize is that we are much more interested (right now) in solving the problem about Me, I and yoU than listen to him babble about six-part fugues and strange loops and incompleteness theorems.
To finish off my own babbling, let me put the MIU problem here. The solution is in the book, but I haven't looked at it. Takes away all the fun. See if you can solve it ( without peeking at the book). If you can, and are sure you have done legally, mail it to me at my gmail address (if you have it, good...if not, don't bother) and I might...just might...let you buy me coffee.

Problem statement:

An alphabet consists of three letters...M, I and U. You are given a string MI to start with. You have the following four rules to work with.Your goal: generate the string MU.

Rule 1: If a string ends with the letter I, you can append a U at the end.
Example: MI becomes MIU.

Rule 2: If a string has the form Mx, where x is the remainder of the string, then it can be transformed to Mxx.
Example: MI can become MII, MIU can become MIUIU.

Rule 3: If the sub-string III occurs anywhere within the string, then it can be replaced by U.
Example: MUIIIU can become MUUU.

Rule 4: If the sub-string UU occurs anywhere within the string, then it can be dropped.
Example: MUUU can become MU.


  1. Aww... no fair.

    Does it count if I "solved" it by myself before I read further back when I swallowed GEB?

    The quotes around 'solved' above are, of course, because (rot13) Vg Pna'g Or Qbar, naq cebivat guvf _vf_ gur fbyhgvba.

  2. Gung vf jung jr gubhtug...ohg bs pbhefr jr pbhyq abg 'cebir' vg!

  3. I don't see why it can't be "proved":

    1. Fvapr abar bs gur ehyrf zbqvsl gur yrnqvat Z, jr pna fnsryl vtaber vg naq pbapragengr ba pbairegvat V gb H. V oryvrir Ubsfgngqre vapyhqrq gur Z whfg fb ur pbhyq fcryy bhg ZH, n fgevat gung cynlf n erpheevat ebyr va gur qvfphffvba ba Mra Ohqquvfz (nzbat bgure guvatf) va gur obbx.

    2. Jr abgvpr gung gur erdhverq svany cnggrea H unf mreb V'f. Gur bayl ehyr gung nyybjf sbe n erqhpgvba va gur ahzore bs V'f vf ehyr 3. Jr erdhver n erqhpgvba sebz bar V gb mreb V'f.

    3. Ehyr 3 pna bayl or hfrq gb bognva H vs vg vf nccyvrq gb gur fgevat VVV be bqq zhygvcyrf bs VVV. Ubjrire, fgnegvat jvgu V, jr abgvpr gung ehyr 2 bayl nyybj sbe n qbhoyvat bs gur ahzore bs Vf va gur fgevat gurl bcrengr hcba. Ehyrf 1 naq 4 unir ab rssrpg ba gur ahzore bs V'f, fb gung na bqq zhygvcyr bs VVV vf arire nggnvarq.

    Gurersber, vg pna'g or qbar.

  4. Ah I see. :) Very enlightening discussion.

  5. To Karthik: Nu tbbq, gung vf jung Fnaqrrc naq V svtherq bhg. Tebbil! :)

    To George: Brave New World my friend, BNW! :)