README.md

Advent of Code 2024 in (Souffle) Datalog

AoC24 using Souffle datalog.

Following last year Advent of Code 2023 in Datalog! And Advent of Code 2022 in Datalog! And Advent of Code 2021 in Datalog!

How to run?

Puzzles are organized by day; answer to day 1 is in day01/day01.dl. The datalog files have .dl extension.

When possible the original input file is used. Otherwise a simple transformation is applied (like numbering the lines) and the input files have .facts extension. The .facts files are produced from the original input file of the puzzle by the prepare.rb script.

Interpreter mode

The quickest way to run a datalog program is to execute Souffle in interpreter mode. The interpreter mode may use N threads with option souffle -j N.

cd day01
# run
souffle --no-preprocessor -D- -F. -I.. day01.dl
# or run with 4 threads
souffle --no-preprocessor -D- -F. -I.. -j 4 day01.dl

Compiled mode

For long programs, or programs with large input, Souffle can generate c++ code.

cd day06

# compile, run on 8 threads and drop the executable
souffle --no-preprocessor -D- -F. -I.. -j 8 -c day06.dl

# compile and keep the executable
souffle --no-preprocessor -D- -F. -I.. -o day06 day06a.dl
# run on 4 threads
./day06 -j 4

What is going on?

By default only the day0x.part1.answer and day0x.part2.answer relations are printed out and provides the answers to the puzzle.

You may want to reveal the content of any of the intermediate relation by adding the appropriate .output directive in the datalog code.