ICFP Programming Contest 2010

The Caml Riders

This is a short description our entry to the ICFP Programming Contest 2010.

Our results

This allowed us to rank 11th, with a score of 2589.113 with 1867 cars solved

Team members

This year, the Caml Riders were (alphabetic order):

Brief description of what we did

Unfortunately, this year's contest did not require to produce any nice picture to show on a web page.

One thing that is worth presenting publicly is one of the car we designed, that was not been solved by any other participant. Producing as many such cars as possible was indeed a key to reach a high score in this contest, but unfortunately we started to submit such these cars only 5 hours before the end. Here is one such car, numbered 159028, displayed in ASCII art using one of our programs.

15 chambers, 4 tanks

 /-0--1-
M
 \-1-

 /-1--0-
A
 \-1^2--0-

 /-1--2-
A
 \-1^2--2-

 /-1--3-
A
 \-1^2--3-

 /-2--1-
M
 \-1-

 /-3--1-
M
 \-1-

 /-1^2--0-
A
 \-1--0-

 /-1^2--2-
A
 \-1--2-

 /-1^2--3-
A
 \-1--3-

 /-0--1--2--3-
A
 \-0--1--2--3-

 /-1--0--2--3-
A
 \-1--0--2--3-

 /-2--0^2--2--0^3--3--0--3--0^2--3-
A
 \-3^12--2--3^2--2--3^9--2--3^7--0--3^15--2--3^2--2--3^13--2--3^9--2--3^18--2--3^28--2--3^52--2--3^3--2--3^6--2--3^8--2--3^18-

 /-0--3^6--0^5--3^3--0--3--2--3--0^6--3--0^2--3--0^3--3--0^2-
A
 \-2^2--3--2^154--0--2^45-

 /-2^2--3--2^154--0--2^45-
A
 \-0--3^6--0^5--3^3--0--3--2--3--0^6--3--0^2--3--0^3--3--0^2-

 /-3^12--2--3^2--2--3^9--2--3^7--0--3^15--2--3^2--2--3^13--2--3^9--2--3^18--2--3^28--2--3^52--2--3^3--2--3^6--2--3^8--2--3^18-
A
 \-2--0^2--2--0^3--3--0--3--0^2--3-
A fuel solution is
         ( 1  39943 )
tank 0 = (          )
         ( 0      1 )

         ( 1   0 )
tank 1 = (       )
         ( 1   0 )

         ( 1 3872 )
tank 2 = (        )
         ( 0    1 )

         ( 1 1191 )
tank 3 = (        )
         ( 0    1 )
Such a difficult car/fuel pair has been generated by encoding into matrices a system of linear Diophantine equations. 16 other cars like this have been submitted, having solutions in dimension 2, with coefficients up of the same order of magnitude. None of them were solved.

18 other of our cars were unsolved by any participants, these were generated using an encoding of equations with very large powers, whose solutions are of dimension 1 but with values typically around 2^{1000}