# Our design

Our code is written in OCaml. We have implemented the core rules, a
scoring system, and a command line interface for the game. Our AI is
quite simple, with a few heuristic to score moves. The AI is basically
a breadth first search, which keeps a set of good move candidates and
explore the reachable states from those. Then, it picks the k-moves
that score the best from the reachable states and continue the search
with those.  After n iterations of this process (i.e., when we have
computed the outcomes of the n next moves), we rank the moves at level
1, according to the best outcome that we found, and play the best
move.

(The most time intensive step of this process is the computation of
the next possible moves, given a configuration. Therefore, we took
some care to memoize those computations. We also fine-tuned the
representation of the configurations, using bit vectors and sparse
representations where appropriate.)

Finally, given a play (a sequence of positions where the pieces are
locked), we use an oracle to change the moves so that the starting
point of the piece and the final position remain the same, while using
words of power if possible.

We do not take into account the memory limit at all. However, we try
to fine tune the depth of our search, based on the amount of time
spent in each turn.

# Running our code

We use:
- ocaml 4.02.1
- the packages ocamlfind, atdgen, bitv, ocurl, cmdliner
- ocamlbuild

Just do make in the main repository, then, cli.native or play_icfp2015
are valid links for the executable that play the game. Consult the
help page these binaries (./cli.native -h for instance) to see the
available options (we have a GUI that makes it possible to play the
game interactively)

# IMPORTANT NOTE

We have tagged the final release of our code, as submitted (tag final on this git repository). However, after the deadline, we realised that it was maybe the case that the program needed to output its results on the standard output. 

Currently, our program outputs the solutions to problem $id in `outputs/$id/$tag.json`. We also collate all the outputs in one big file at `outputs/scoreboard` (accessing this file from multiple process might be an issue, as accesses are not locked). The good way to get all the results from our program would be to read all the json files in `outputs`.