Rabbits and Pheasants

Setup

Mix.install([
  {:exhort, git: "https://github.com/elixir-or-tools/exhort"}
])

use Exhort.SAT.Builder

Model

response =
  Builder.new()
  |> Builder.def_int_var("r", {0, 100})
  |> Builder.def_int_var("p", {0, 100})
  |> Builder.constrain("r" + "p" == 20)
  |> Builder.constrain(4 * "r" + 2 * "p" == 56)
  |> Builder.build()
  |> Model.solve()