- sudoku in as many languages as possible
- solvers should accept a single command line argument that's a filename
- `inputs/*` files generated by `generator`
- every two lines represents one puzzle, the first is the open puzzle, the second is the expected solution

bash: done, but very slow, working on an optimized version that doesn't copy the puzzle every iteration
c: done, fast reference solution
cpp: done, need to try translating the fast reference solution
fortran: done, fast reference solution
go: done
haskell: done
java: done
javascript: done
kotlin: done
objective-c: done
ocaml: done
r: done
ruby: done
rust: done
swift: done
typescript: done

elixir: in progress
erlang: todo
j: todo
lua: in progress
prolog: todo
python: need to clean up
scheme: in progress
zig: todo