Finished day 22

Author: devries

README.md

@@ -1,7 +1,7 @@
 # Advent of Code 2024
 
 [![Tests](https://github.com/devries/advent_of_code_2024/actions/workflows/test.yml/badge.svg)](https://github.com/devries/advent_of_code_2024/actions/workflows/test.yml)
-[![Stars: 41](https://img.shields.io/badge/⭐_Stars-41-yellow)](https://adventofcode.com/2024)
+[![Stars: 43](https://img.shields.io/badge/⭐_Stars-43-yellow)](https://adventofcode.com/2024)
 
 This year I am going to try to do Advent of Code in  [Gleam](https://gleam.run).
 To run a day's problems use the command
@@ -39,4 +39,5 @@ information.
 - [Day 18](https://adventofcode.com/2024/day/18): [⭐ ⭐ solution](src/day18/solution.gleam)
 - [Day 19](https://adventofcode.com/2024/day/19): [⭐ ⭐ solution](src/day19/solution.gleam)
 - [Day 20](https://adventofcode.com/2024/day/20): [⭐ ⭐ solution](src/day20/solution.gleam)
-- [Day 21](https://adventofcode.com/2024/day/21): [⭐   solution](src/day21/solution.gleam)
+- [Day 21](https://adventofcode.com/2024/day/21): [⭐    solution](src/day21/solution.gleam)
+- [Day 22](https://adventofcode.com/2024/day/22): [⭐ ⭐ solution](src/day22/solution.gleam)

gleam.toml

@@ -21,6 +21,7 @@ birl = ">= 1.7.1 and < 2.0.0"
 gleam_erlang = ">= 0.33.0 and < 1.0.0"
 gleam_otp = ">= 0.16.0 and < 1.0.0"
 envoy = ">= 1.0.2 and < 2.0.0"
+gleam_yielder = ">= 1.1.0 and < 2.0.0"
 
 [dev-dependencies]
 gleeunit = ">= 1.0.0 and < 2.0.0"

inputs

@@ -10,6 +10,7 @@ packages = [
   { name = "gleam_otp", version = "0.16.0", build_tools = ["gleam"], requirements = ["gleam_erlang", "gleam_stdlib"], otp_app = "gleam_otp", source = "hex", outer_checksum = "FA0EB761339749B4E82D63016C6A18C4E6662DA05BAB6F1346F9AF2E679E301A" },
   { name = "gleam_regexp", version = "1.0.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "gleam_regexp", source = "hex", outer_checksum = "A3655FDD288571E90EE9C4009B719FEF59FA16AFCDF3952A76A125AF23CF1592" },
   { name = "gleam_stdlib", version = "0.45.0", build_tools = ["gleam"], requirements = [], otp_app = "gleam_stdlib", source = "hex", outer_checksum = "206FCE1A76974AECFC55AEBCD0217D59EDE4E408C016E2CFCCC8FF51278F186E" },
+  { name = "gleam_yielder", version = "1.1.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "gleam_yielder", source = "hex", outer_checksum = "8E4E4ECFA7982859F430C57F549200C7749823C106759F4A19A78AEA6687717A" },
   { name = "gleeunit", version = "1.2.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "gleeunit", source = "hex", outer_checksum = "F7A7228925D3EE7D0813C922E062BFD6D7E9310F0BEE585D3A42F3307E3CFD13" },
   { name = "ranger", version = "1.3.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "ranger", source = "hex", outer_checksum = "B8F3AFF23A3A5B5D9526B8D18E7C43A7DFD3902B151B97EC65397FE29192B695" },
   { name = "simplifile", version = "2.2.0", build_tools = ["gleam"], requirements = ["filepath", "gleam_stdlib"], otp_app = "simplifile", source = "hex", outer_checksum = "0DFABEF7DC7A9E2FF4BB27B108034E60C81BEBFCB7AB816B9E7E18ED4503ACD8" },
@@ -23,5 +24,6 @@ gleam_erlang = { version = ">= 0.33.0 and < 1.0.0" }
 gleam_otp = { version = ">= 0.16.0 and < 1.0.0" }
 gleam_regexp = { version = ">= 1.0.0 and < 2.0.0" }
 gleam_stdlib = { version = ">= 0.34.0 and < 2.0.0" }
+gleam_yielder = { version = ">= 1.1.0 and < 2.0.0" }
 gleeunit = { version = ">= 1.0.0 and < 2.0.0" }
 simplifile = { version = ">= 2.2.0 and < 3.0.0" }

manifest.toml

@@ -0,0 +1,116 @@
+import gleam/dict.{type Dict}
+import gleam/int
+import gleam/io
+import gleam/list
+import gleam/pair
+import gleam/result
+import gleam/yielder
+import internal/aoc_utils
+
+pub fn main() {
+  let filename = "inputs/day22.txt"
+
+  let lines_result = aoc_utils.read_lines(from: filename)
+  case lines_result {
+    Ok(lines) -> {
+      // If the file was converting into a list of lines
+      // successfully then run each part of the problem
+      aoc_utils.run_part_and_print("Part 1", fn() { solve_p1(lines) })
+      aoc_utils.run_part_and_print("Part 2", fn() { solve_p2(lines) })
+    }
+    Error(_) -> io.println("Error reading file")
+  }
+}
+
+// Part 1
+pub fn solve_p1(lines: List(String)) -> Result(String, String) {
+  use numberlist <- result.map({
+    lines
+    |> list.try_map(int.parse)
+    |> result.replace_error("Unable to parse input")
+  })
+
+  numberlist
+  |> list.map(step_times(_, 2000))
+  |> int.sum
+  |> int.to_string
+}
+
+// Part 2
+pub fn solve_p2(lines: List(String)) -> Result(String, String) {
+  use numberlist <- result.try({
+    lines
+    |> list.try_map(int.parse)
+    |> result.replace_error("Unable to parse input")
+  })
+
+  use best_pair <- result.map({
+    numberlist
+    |> list.map(find_sequence_sets(_, 2000))
+    |> list.map(build_values)
+    |> list.fold(dict.new(), fn(da, d) {
+      dict.to_list(d)
+      |> list.fold(da, fn(da, tup) {
+        let #(seq, price) = tup
+        let value = dict.get(da, seq) |> result.unwrap(0)
+        dict.insert(da, seq, value + price)
+      })
+    })
+    |> dict.to_list
+    |> list.sort(fn(a, b) { int.compare(a.1, b.1) })
+    |> list.last
+    |> result.replace_error("Something went wront")
+  })
+
+  pair.second(best_pair)
+  |> int.to_string
+}
+
+pub fn step(start: Int) -> Int {
+  let first = int.bitwise_exclusive_or({ start * 64 }, start) % 16_777_216
+  let second = int.bitwise_exclusive_or({ first / 32 }, first) % 16_777_216
+  int.bitwise_exclusive_or({ second * 2048 }, second) % 16_777_216
+}
+
+fn step_times(start: Int, times: Int) -> Int {
+  case times {
+    0 -> start
+    n -> step_times(step(start), n - 1)
+  }
+}
+
+fn price_sequence(start: Int, length: Int) -> List(Int) {
+  yielder.unfold(start, fn(v) {
+    let r = step(v)
+    yielder.Next(v, r)
+  })
+  |> yielder.take(length + 1)
+  |> yielder.to_list
+  |> list.map(fn(v) { v % 10 })
+}
+
+fn differences(numbers: List(Int)) -> List(Int) {
+  list.window_by_2(numbers)
+  |> list.map(fn(tup) { tup.1 - tup.0 })
+}
+
+fn find_sequence_sets(start: Int, length: Int) -> List(#(Int, List(Int))) {
+  let prices = price_sequence(start, length)
+
+  let sequences = differences(prices) |> list.window(4)
+
+  list.zip(list.drop(prices, 4), sequences)
+}
+
+fn build_values(sequences: List(#(Int, List(Int)))) -> Dict(List(Int), Int) {
+  list.fold(sequences, dict.new(), fn(d, tup) {
+    let #(price, sequence) = tup
+
+    case dict.get(d, sequence) {
+      Ok(_) -> d
+      Error(Nil) -> {
+        dict.insert(d, sequence, price)
+      }
+    }
+  })
+}

src/day22/solution.gleam

@@ -13,9 +13,9 @@ pub fn part1_test() {
   solution.solve_p1(lines)
   |> should.equal(Ok("126384"))
 }
-
-pub fn part2_test() {
-  let lines = string.split(testinput, "\n")
-  solution.solve_p2(lines)
-  |> should.equal(Ok(""))
-}
+// Uncomment when done
+// pub fn part2_test() {
+//   let lines = string.split(testinput, "\n")
+//   solution.solve_p2(lines)
+//   |> should.equal(Ok(""))
+// }

test/day21_test.gleam

@@ -0,0 +1,43 @@
+import day22/solution
+import gleam/io
+import gleam/list
+import gleam/string
+import gleam/yielder
+import gleeunit/should
+
+const testinput = "1
+10
+100
+2024"
+
+pub fn part1_test() {
+  let lines = string.split(testinput, "\n")
+  solution.solve_p1(lines)
+  |> should.equal(Ok("37327623"))
+}
+
+const testinput_p2 = "1
+2
+3
+2024"
+
+pub fn part2_test() {
+  let lines = string.split(testinput_p2, "\n")
+  solution.solve_p2(lines)
+  |> should.equal(Ok("23"))
+}
+
+const testsequence = [
+  15_887_950, 16_495_136, 527_345, 704_524, 1_553_684, 12_683_156, 11_100_544,
+  12_249_484, 7_753_432, 5_908_254,
+]
+
+pub fn step_test() {
+  yielder.unfold(123, fn(v) {
+    let r = solution.step(v)
+    yielder.Next(r, r)
+  })
+  |> yielder.take(list.length(testsequence))
+  |> yielder.to_list
+  |> should.equal(testsequence)
+}