From f69e98cfc4c00b0e0d87c6aaf1d90d436f1d31bf Mon Sep 17 00:00:00 2001
From: Jeremy Kaplan <jdkaplan@metagram.net>
Date: Thu, 30 Nov 2023 21:51:43 -0800
Subject: [PATCH] 2023 Day 1

---
 2023/.gitignore |  1 +
 2023/day01.nim  | 58 +++++++++++++++++++++++++++++++++++++++++++++++++
 README.md       |  2 +-
 3 files changed, 60 insertions(+), 1 deletion(-)
 create mode 100644 2023/.gitignore
 create mode 100644 2023/day01.nim

diff --git a/2023/.gitignore b/2023/.gitignore
new file mode 100644
index 0000000..59ded47
--- /dev/null
+++ b/2023/.gitignore
@@ -0,0 +1 @@
+/input
diff --git a/2023/day01.nim b/2023/day01.nim
new file mode 100644
index 0000000..92ff2d0
--- /dev/null
+++ b/2023/day01.nim
@@ -0,0 +1,58 @@
+const numbers = "0123456789"
+const words = @[
+  "one",
+  "two",
+  "three",
+  "four",
+  "five",
+  "six",
+  "seven",
+  "eight",
+  "nine",
+]
+
+proc part1(): int =
+  let f = open("input/day01.txt")
+  defer: f.close()
+
+  var line: string
+  while f.readLine(line):
+    var nums: seq[int] = @[]
+    for char in line:
+      if char in numbers:
+        nums.add(char.int - '0'.int)
+
+    result += 10 * nums[0] + nums[^1]
+
+proc extractNumsOverlap(line: string): seq[int] =
+  var i = 0
+  while i < line.len:
+    let char = line[i]
+
+    if char in numbers:
+      result.add(char.int - '0'.int)
+      inc i
+      continue
+
+    for n, word in words:
+      let
+        size = word.len
+        cap = min(i + size, line.len)
+      if line[i..<cap] == word:
+        result.add(n+1)
+        break
+    inc i
+
+proc part2(): int =
+  let f = open("input/day01.txt")
+  defer: f.close()
+
+  var line: string
+  while f.readLine(line):
+    let
+      nums = extractNumsOverlap(line)
+
+    result += 10 * nums[0] + nums[^1]
+
+echo part1()
+echo part2()
diff --git a/README.md b/README.md
index 13d16ff..d1a39f4 100644
--- a/README.md
+++ b/README.md
@@ -8,9 +8,9 @@ I like solving the [Advent of Code](https://adventofcode.com/) challenges every
 - 2020: Elixir
 - 2021: Go
 - 2022: Rust (Again! v1.65, 2021 edition)
+- 2023: Nim
 
 Languages I'd like to use for the future or TODO years:
 - J (or other APL-like)
 - Haskell
 - Zig
-- Nim