Advent of Code 2017 Main Page | Tests 2015 | 2016 | 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 | 2024 🏆 34/50 Day Problem Page Status Difficulty Solution Page Test Page Tags 1 Inverse Captcha 🥇 ❄️ day_01.ex day_01_test.exs sliding-window, rust 2 Corruption Checksum 🥇 ❄️ day_02.ex day_02_test.exs arithmetic, sequence, rust 3 Spiral Memory 🥇 ❄️ ❄️ ❄️ day_03.ex day_03_test.exs spiral, matrix 4 High-Entropy Passphrases 🥇 ❄️ day_04.ex day_04_test.exs validation, rust 5 A Maze of Twisty Trampolines, All Alike 🥇 ❄️ ❄️ day_05.ex day_05_test.exs not-fast-enough, random-access 6 Memory Reallocation 🥇 ❄️ ❄️ ❄️ day_06.ex day_06_test.exs sequence, reduction 7 Recursive Circus 🥈 ❄️ ❄️ ❄️ day_07.ex day_07_test.exs tree 8 I Heard You Like Registers 🥇 ❄️ ❄️ day_08.ex day_08_test.exs op-code 9 Stream Processing 🥇 ❄️ ❄️ day_09.ex day_09_test.exs fsm 10 Knot Hash 🥇 ❄️ ❄️ day_10.ex day_10_test.exs hash 11 Hex Ed 🥇 ❄️ ❄️ ❄️ ❄️ day_11.ex day_11_test.exs hexagon 12 Digital Plumber 🥇 ❄️ ❄️ day_12.ex day_12_test.exs disjoint-set 13 Packet Scanners 🥇 ❄️ ❄️ day_13.ex day_13_test.exs sequence, slow 14 Disk Defragmentation 🥈 ❄️ ❄️ ❄️ day_14.ex day_14_test.exs not-fast-enough, half-done, hash 15 Dueling Generators 🥇 ❄️ ❄️ ❄️ ❄️ day_15.ex day_15_test.exs number-theory, bitwise, slow 16 Permutation Promenade 🥇 ❄️ ❄️ ❄️ day_16.ex day_16_test.exs op-code, count 17 Spinlock 🥇 ❄️ ❄️ ❄️ day_17.ex day_17_test.exs vector, random-access, not-fast-enough 18 Duet 🥈 ❄️ ❄️ ❄️ day_18.ex day_18_test.exs data-modelling, op-code, half-done 23 Coprocessor Conflagration 🥈 ❄️ ❄️ ❄️ day_23.ex day_23_test.exs op-code