refactor: extract mod, lcm, and gcd to lib

Author: mfulton26

2022/day/24/part/1/solve.ts

@@ -1,5 +1,8 @@
 import type { Grid, ReadonlyGrid } from "../../grid.ts";
 
+import lcm from "../../../../../lib/lcm.ts";
+import mod from "../../../../../lib/mod.ts";
+
 const charToDirection = {
   "^": { x: 0, y: -1 },
   "v": { x: 0, y: 1 },
@@ -13,19 +16,6 @@ function parseGrid(text: string): ReadonlyGrid {
   );
 }
 
-function gcd(a: number, b: number): number {
-  while (b) [a, b] = [b, a % b];
-  return a;
-}
-
-function lcm(a: number, b: number) {
-  return a * b / gcd(a, b);
-}
-
-function mod(n: number, d: number) {
-  return ((n % d) + d) % d;
-}
-
 function calculateGrid(initialGrid: ReadonlyGrid, step: number): ReadonlyGrid {
   const { length: height, 0: { length: width } } = initialGrid;
   const result = structuredClone(initialGrid) as Grid;

2022/day/24/part/2/solve.ts

@@ -1,25 +1,15 @@
 import type { Grid, ReadonlyGrid } from "../../grid.ts";
 
+import lcm from "../../../../../lib/lcm.ts";
+import mod from "../../../../../lib/mod.ts";
+
 const charToDirection = {
   "^": { x: 0, y: -1 },
   "v": { x: 0, y: 1 },
   "<": { x: -1, y: 0 },
   ">": { x: 1, y: 0 },
 };
 
-function gcd(a: number, b: number): number {
-  while (b) [a, b] = [b, a % b];
-  return a;
-}
-
-function lcm(a: number, b: number) {
-  return a * b / gcd(a, b);
-}
-
-function mod(n: number, d: number) {
-  return ((n % d) + d) % d;
-}
-
 function calculateGrid(initialGrid: ReadonlyGrid, step: number): ReadonlyGrid {
   const { length: height, 0: { length: width } } = initialGrid;
   const result = structuredClone(initialGrid) as Grid;

2023/day/20/part/2/solve.ts

@@ -1,3 +1,5 @@
+import lcm from "../../../../../lib/lcm.ts";
+
 type Pulse = { source: string; type: "low" | "high"; destination: string };
 
 type CommonModuleProps = {
@@ -18,15 +20,6 @@ type UntypedModule = CommonModuleProps & {
 };
 type Module = FlipFlopModule | ConjunctionModule | UntypedModule;
 
-function gcd(a: number, b: number): number {
-  while (b) [a, b] = [b, a % b];
-  return a;
-}
-
-function lcm(a: number, b: number) {
-  return a * b / gcd(a, b);
-}
-
 export default function solve(input: string) {
   const modules = input.split("\n").map<Module>((line) => {
     const [left, right] = line.split(" -> ");

2023/day/21/part/2/solve.ts

@@ -1,16 +1,14 @@
 import { BinaryHeap } from "std/data_structures/binary_heap.ts";
 
+import mod from "../../../../../lib/mod.ts";
+
 const directions = [
   { x: 0, y: 1 },
   { x: 0, y: -1 },
   { x: -1, y: 0 },
   { x: 1, y: 0 },
 ];
 
-function mod(a: number, b: number) {
-  return ((a % b) + b) % b;
-}
-
 function _solve(input: string, { steps = 26501365 } = {}) {
   const map = input.split("\n");
   const { length: height, 0: { length: width } } = map;

2023/day/8/part/2/solve.ts

@@ -1,3 +1,5 @@
+import lcm from "../../../../../lib/lcm.ts";
+
 function parseDocuments(text: string) {
   const [instructionsText, networkText] = text.split("\n\n");
   const instructions = Array.from(
@@ -12,15 +14,6 @@ function parseDocuments(text: string) {
   return { instructions, network };
 }
 
-function gcd(a: number, b: number): number {
-  while (b) [a, b] = [b, a % b];
-  return a;
-}
-
-function lcm(a: number, b: number) {
-  return a * b / gcd(a, b);
-}
-
 export default function solve(input: string) {
   const { instructions, network } = parseDocuments(input);
   return Array.from(network.keys())

2024/day/14/part/1/solve.ts

@@ -1,3 +1,5 @@
+import mod from "../../../../../lib/mod.ts";
+
 const regExp = /^p=(?<px>\d+),(?<py>\d+) v=(?<vx>-?\d+),(?<vy>-?\d+)$/gm;
 
 export default function solve(
@@ -15,7 +17,3 @@ export default function solve(
   }
   return quadrantCounts.reduce((product, count) => product * count, 1);
 }
-
-function mod(a: number, b: number) {
-  return ((a % b) + b) % b;
-}

lib/gcd.ts

@@ -0,0 +1,4 @@
+export default function gcd(a: number, b: number): number {
+  while (b) [a, b] = [b, a % b];
+  return a;
+}

lib/lcm.ts

@@ -0,0 +1,5 @@
+import gcd from "./gcd.ts";
+
+export default function lcm(a: number, b: number) {
+  return a * b / gcd(a, b);
+}

lib/mod.ts

@@ -0,0 +1,3 @@
+export default function mod(n: number, d: number) {
+  return ((n % d) + d) % d;
+}