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Ponder This

May 2013

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Ponder This Challenge:

Define a program to be a list of commands, each command of the form
Variable_1 <=- Variable_2 Operation constant
or
Variable_1 <=- Variable_2 Operation Variable_3
where operation can be either addition, multiplication or modulo.

Here is an example of a program which computes the function
f(x) = 1+x+x^2+x^4 (modulo 2233393)

a=x*47518
b=a*a
c=x+1
d=c+b
e=b*b
f=e+d
g=f mod 2233393

Find another program which computes the same function which uses a multiplying two variables at most twice and its last two commands are: a multiplication of two variables and a modulo computation.


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Challenge: 05/01/2013 @ 01:00 PM EST
Solution: 06/03/2013 @ 01:00 PM EST
List Updated: 05/01/2013 @ 01:00 PM EST

People who answered correctly:

*Jan Fricke (04/30/2013 02:36 PM EDT)
Thomas Mack (05/01/2013 12:43 AM EDT)
János Kramár (05/01/2013 01:54 AM EDT)
Siji Feng (05/01/2013 02:02 AM EDT)
Robin Ryder (05/01/2013 02:15 AM EDT)
*Radu-Alexandru Todor (05/01/2013 05:07 AM EDT)
*Florian Fischer (05/01/2013 05:38 AM EDT)
Frederik Kaster (05/01/2013 06:51 AM EDT)
Adrian Orzepowski (05/01/2013 07:22 AM EDT)
Pete Gerritson (05/01/2013 10:39 AM EDT)
Alan Murray (05/01/2013 11:14 AM EDT)
Pavan Vaswani (05/01/2013 01:41 PM EDT)
Paul Safier (05/02/2013 02:35 AM EDT)
Arthur Vause (05/02/2013 08:20 AM EDT)
Peter Holdsworth (05/02/2013 12:05 PM EDT)
Don Dodson & Dave Dodson (05/03/2013 12:28 AM EDT)
Siva Dirisala (05/03/2013 03:44 AM EDT)
Joseph DeVincentis (05/03/2013 07:38 AM EDT)
Andrew Gacek (05/03/2013 09:03 AM EDT)
Olivier Mercier (05/03/2013 09:18 AM EDT)
Alex Fleischer (05/03/2013 10:57 AM EDT)
John Tromp (05/03/2013 12:52 PM EDT)
*Eric Harley (05/03/2013 02:00 PM EDT)
David Greer (05/03/2013 09:40 PM EDT)
Yasodhar Patnaik (05/03/2013 11:28 PM EDT)
Albert Stadler (05/04/2013 12:16 PM EDT)
*Alex Wagner (05/04/2013 02:42 PM EDT)
Xianchao Xie (05/04/2013 07:29 PM EDT)
Gerhard + Klaus Hoffmann (05/04/2013 02:49 PM EDT)
Liubing Yu (05/05/2013 01:23 PM EDT)
Antonio García Astudillo (05/05/2013 04:05 PM EDT)
Joe Klobusicky (05/05/2013 04:59 PM EDT)
Amos Guler (05/06/2013 09:45 AM EDT)
Peijie You (05/07/2013 01:15 AM EDT)
Pushkar S Joglekar (05/07/2013 04:58 AM EDT)
Harald Bögeholz (05/07/2013 02:07 PM EDT)
Clive Tong (05/07/2013 02:43 PM EDT)
Dan Dima (05/07/2013 03:57 PM EDT)
Javier Rodriguez (05/07/2013 05:09 PM EDT)
*Armin Krauss (05/08/2013 01:03 PM EDT)
Todd Will (05/08/2013 03:09 PM EDT)
Rodrigo Exterckötter Tjäder (05/08/2013 08:14 PM EDT)
Swaraj Dash (05/07/2013 09:49 AM EDT)
Adir HaCohen (05/09/2013 07:00 PM EDT)
*Lorenzo Gianferrari Pini (05/10/2013 07:14 AM EDT)
Mark Pervovskiy (05/10/2013 09:44 AM EDT)
*Álvaro Begué (05/10/2013 09:54 AM EDT)
*I. J. Kennedy (05/10/2013 12:01 PM EDT)
Daniel Branscombe (05/10/2013 08:31 PM EDT)
Rogerio Ponce (05/11/2013 04:33 AM EDT)
Seung Min Park (05/12/2013 09:47 AM EDT)
*Antoine Comeau (05/12/2013 04:01 PM EDT)
Andreas Stiller (05/13/2013 06:24 AM EDT)
*Serge Gautier (05/13/2013 04:04 PM EDT)
*Motty Porat (05/15/2013 03:53 PM EDT)
*Tom Harley (05/15/2013 04:23 PM EDT)
Zilin Jiang (05/15/2013 10:57 PM EDT)
Andreas Razen (05/19/2013 03:46 AM EDT)
Jason Lee & Jacob Woolcutt (05/19/2013 09:36 AM EDT)
Franza Cavalcante Jr (05/22/2013 11:09 AM EDT)
Rongheng Lin (05/23/2013 01:38 PM EDT)
Nyles Heise (05/23/2013 11:01 PM EDT)
William Kang (05/25/2013 08:33 AM EDT)
Ian Wright (05/25/2013 09:15 AM EDT)
Daniel Bitin (05/26/2013 10:00 AM EDT)
Ehud Schreiber (05/27/2013 01:44 AM EDT)
Michael Lim (05/29/2013 08:21 PM EDT)
Sergey Grishaev (06/01/2013 06:05 AM EDT)


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