From ad415c5f7002b21a3ae19a272c3d3bab18b192b7 Mon Sep 17 00:00:00 2001
From: Joshua Cook <joshua_cook@vrtx.com>
Date: Tue, 16 Jan 2024 06:56:10 -0500
Subject: [PATCH] refactor: move LCM func to public mod

---
 src/lib.rs             |  2 ++
 src/math_utils.rs      | 10 ++++++++++
 src/solutions/day08.rs | 18 ++++--------------
 3 files changed, 16 insertions(+), 14 deletions(-)
 create mode 100644 src/math_utils.rs

diff --git a/src/lib.rs b/src/lib.rs
index 9aae442..46ab22a 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,5 +1,7 @@
 mod data;
+mod math_utils;
 pub mod solutions;
+
 use thiserror::Error;
 
 #[derive(Error, Debug)]
diff --git a/src/math_utils.rs b/src/math_utils.rs
new file mode 100644
index 0000000..30a4e8d
--- /dev/null
+++ b/src/math_utils.rs
@@ -0,0 +1,10 @@
+use num::integer;
+
+// Algorithm source: https://www.geeksforgeeks.org/lcm-of-given-array-elements/
+pub fn lcm(a: Vec<u64>) -> u64 {
+    let mut lcm = a[0];
+    for i in a.iter() {
+        lcm = integer::div_floor(lcm * *i, integer::gcd(lcm, *i));
+    }
+    lcm
+}
diff --git a/src/solutions/day08.rs b/src/solutions/day08.rs
index 913a1aa..1eb067e 100644
--- a/src/solutions/day08.rs
+++ b/src/solutions/day08.rs
@@ -1,6 +1,6 @@
 use crate::data::load;
+use crate::math_utils;
 use lazy_static::lazy_static;
-use num::integer::div_floor;
 use regex::Regex;
 use std::collections::hash_map::Entry;
 use std::collections::{HashMap, HashSet};
@@ -193,15 +193,6 @@ fn make_state_map(
     }
 }
 
-// Algorithm source: https://www.geeksforgeeks.org/lcm-of-given-array-elements/
-fn lcm(a: Vec<u64>) -> u64 {
-    let mut lcm = a[0];
-    for i in a.iter() {
-        lcm = div_floor(lcm * *i, num::integer::gcd(lcm, *i));
-    }
-    lcm
-}
-
 pub fn puzzle_2(input: &str) -> Result<u64, PuzzleErr> {
     let (directions, graph) = parse_input(input)?;
 
@@ -224,10 +215,9 @@ pub fn puzzle_2(input: &str) -> Result<u64, PuzzleErr> {
         .map(|n| make_state_map(n, &end_nodes, &graph, directions.clone()))
         .collect::<Vec<_>>();
 
-    Ok(lcm(state_maps
-        .iter()
-        .map(|sm| sm.loop_size as u64)
-        .collect()))
+    Ok(math_utils::lcm(
+        state_maps.iter().map(|sm| sm.loop_size as u64).collect(),
+    ))
 }
 
 pub fn main(data_dir: &str) {