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authorHJ <thechairman@thechairman.info>2021-12-09 18:05:04 -0500
committerHJ <thechairman@thechairman.info>2021-12-09 18:05:04 -0500
commit527bc4762f9c66c9244f0ac1fbee6357478ac9ef (patch)
treeecd3ffc97de5aab201699f93aab1e0417ac3d25d /2021/day-02
downloadgleam_aoc-527bc4762f9c66c9244f0ac1fbee6357478ac9ef.tar.gz
gleam_aoc-527bc4762f9c66c9244f0ac1fbee6357478ac9ef.zip
putting all my solutions together in 1 repository
Diffstat (limited to '2021/day-02')
-rw-r--r--2021/day-02/day-02.ex32
-rw-r--r--2021/day-02/day-02.rkt39
2 files changed, 71 insertions, 0 deletions
diff --git a/2021/day-02/day-02.ex b/2021/day-02/day-02.ex
new file mode 100644
index 0000000..d37ab05
--- /dev/null
+++ b/2021/day-02/day-02.ex
@@ -0,0 +1,32 @@
+defmodule Day02 do
+ def part_one(data) do
+ data
+ |> Enum.reduce(%{pos: 0, dep: 0}, &method_one/2)
+ |> get_answer()
+ end
+
+ def part_two(data) do
+ data
+ |> Enum.reduce(%{pos: 0, dep: 0, aim: 0}, &method_two/2)
+ |> get_answer()
+ end
+
+ defp method_one({:forward, x}, s), do: %{s | pos: s.pos + x}
+ defp method_one({:up, x}, s), do: %{s | dep: s.dep - x}
+ defp method_one({:down, x}, s), do: %{s | dep: s.dep + x}
+
+ defp method_two({:forward, x}, s), do: %{s | pos: s.pos + x, dep: s.dep + s.aim * x}
+ defp method_two({:up, x}, s), do: %{s | aim: s.aim - x}
+ defp method_two({:down, x}, s), do: %{s | aim: s.aim + x}
+
+ defp get_answer(s), do: s.pos * s.dep
+end
+
+data =
+ File.read!("day-02/input.txt")
+ |> String.split("\n", trim: true)
+ |> Enum.map(&String.split/1)
+ |> Enum.map(fn [dir, amt] -> {String.to_atom(dir), String.to_integer(amt)} end)
+
+Day02.part_one(data) |> IO.inspect()
+Day02.part_two(data) |> IO.inspect()
diff --git a/2021/day-02/day-02.rkt b/2021/day-02/day-02.rkt
new file mode 100644
index 0000000..dbd1275
--- /dev/null
+++ b/2021/day-02/day-02.rkt
@@ -0,0 +1,39 @@
+#lang racket
+(require advent-of-code
+ threading
+ algorithms)
+
+(define motion-data
+ (~> (open-aoc-input (find-session) 2021 2 #:cache (string->path "./cache"))
+ (port->list read _)
+ (chunks-of _ 2)))
+
+;; part 1
+(for/fold ([depth 0]
+ [position 0]
+ #:result (* depth position))
+ ([motion (in-list motion-data)])
+ (match motion
+ [(list 'forward x) (values depth
+ (+ position x))]
+ [(list 'up x) (values (- depth x)
+ position)]
+ [(list 'down x) (values (+ depth x)
+ position)]))
+
+;; part 2
+(for/fold ([aim 0]
+ [depth 0]
+ [position 0]
+ #:result (* depth position))
+ ([motion (in-list motion-data)])
+ (match motion
+ [(list 'forward x) (values aim
+ (+ depth (* aim x))
+ (+ position x))]
+ [(list 'up x) (values (- aim x)
+ depth
+ position)]
+ [(list 'down x) (values (+ aim x)
+ depth
+ position)])) \ No newline at end of file