Midterm fall 2009 cs 4500
This presentation is the property of its rightful owner.
Sponsored Links
1 / 8

Midterm Fall 2009 CS 4500 PowerPoint PPT Presentation


  • 52 Views
  • Uploaded on
  • Presentation posted in: General

Midterm Fall 2009 CS 4500. Karl Lieberherr. Black box for TBall. Want to use it to play Slow Pitch Softball. Slow Pitch Softball is reducible to TBall . The black box contains: TBallOffer , TBallAccept , TBallProvide , TBallSolve Translation T: SPS -> TBall

Download Presentation

Midterm Fall 2009 CS 4500

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Midterm fall 2009 cs 4500

Midterm Fall 2009CS 4500

Karl Lieberherr


Black box for tball

Black box for TBall

  • Want to use it to play Slow Pitch Softball.

  • Slow Pitch Softball is reducible to TBall.

  • The black box contains:

    • TBallOffer, TBallAccept, TBallProvide, TBallSolve

  • Translation T: SPS -> TBall

    • Accept(SPS c) is winning iffTBallAccept(T(c)) is winning

    • T is fast (polynomial time)


Similar situation from theory of computation

Similar situation from Theory of Computation

  • Black box for 3-Coloring a graph.

  • We want to use it to solve the 3-SAT problem.

  • The black box contains: HasA-3Coloring(graph g)

  • Translation T: 3-SAT -> 3-Coloring

    • s is satisfiable iff T(s) has a 3-Coloring

    • T is fast (polynomial time)


Black box for fast pitch softball fps

Black box for Fast Pitch Softball (FPS)

  • Want to use it to play Midterm Softball (MS).

  • The black box contains:

    • TBallOffer, TBallAccept, TBallProvide, TBallSolve

  • Translation T: MS-> FPS

    • Accept(MS c) is winning iffFPSAccept(T(c)) is winning

    • T is fast (polynomial time)


St slow pitch softball sps is reducible to tball

ST: Slow Pitch Softball (SPS) is reducible to TBall

  • Offer

    • Use TBallOffer to create TBall challenge. Add some implied relations.

  • Accept(SPS c)

    • TBallAccept(ST(c))

  • Provide(SPS c)

    • TBallProvide(ST(c))

  • Solve(SPS c, Problem p)

    • p’=Filter ST(c) constraints in p; TBallSolve(ST(c), p’)


Mf midterm softball ms is reducible to fast pitch softball fps

MF: Midterm Softball (MS) is reducible to Fast Pitch Softball (FPS)

MFC: Translate Midterm challenge to (R1,R2) Fast Pitch Softball challenge.

MFP: MS problems -> FPS problems

FMP: FPS_MS problems -> MS problems

  • Offer

    • Create MS challenge mch; Use FPSBreakEven(MFC(mch)) to compute price

  • Accept(MS c)

    • FPSAccept(MFC(c))

  • Provide(MS c)

    • FMP(FPSProvide(MFC(c)))

  • Solve(MS c, Problem p)

    • FPSSolve(MFC(c), MFP(p))


Playing scg scholar for ms fps

Playing SCG-Scholar for MS->FPS

  • Alice claims: I understand MS->FPS

  • Bob opposes Alice.

  • Bob gives her a winning MS challenge

  • Alice translates it to FPS

  • The FPS challenge is not winning. Alice loses; she has demonstrated that she does not understand MS->FPS.


Playing scg scholar for ms fps another variant code review

Playing SCG-Scholar for MS->FPS:Another variant: code review

  • Alice claims: I have a correct translation T:MS-FPS.

  • Bob opposes Alice.

  • Alice gives her code for T to Bob.

  • Bob does a code review of T and finds an input where T fails.

  • Bob wins: he has demonstrated to Alice that she does not have a correct translation


  • Login