Past years 2015 Ruby (complete) C++ (complete) D (complete) Haskell (complete) Rust (complete) 2016 Ruby (complete) Haskell (24/25 complete) 2017 Ruby (complete) Haskell (24/25 complete) 2018 Ruby (complete) Haskell (20/25 complete) 2019 Ruby (complete) Haskell (24/25 complete) Rust (complete) 2020 Ruby (complete) Haskell (complete) Rust (selected problems only, not intending to complete) 2021 Ruby (complete) Haskell (24/25 complete) 2022 Ruby (complete) Haskell (complete) 2023 Ruby (complete) Haskell (complete) Rust (selected problems only, not intending to complete)