part 2, crummy

2022/15/part1.js

@@ -11,7 +11,7 @@ const readInput = (...args) =>
         readFile(...args),
         (lines) => lines.split("\n"),
         R.compact, // remove last line
-        R.map(line => line.match(/x=.*?y=\d+/g).map(str =>
+        R.map(line => line.match(/x=-?.*?y=-?\d+/g).map(str =>
             str.match(/-?\d+/g).map(x => parseInt(x))).map(
                 coords => V(coords)
             )

2022/15/part2.js

@@ -1,4 +1,24 @@
 import * as R from "remeda";
+import V from '@yanick/vyktor';
 
+export const findBeacon = max => entries => {
 
-export default () => {};
+    const nonGrata = R.uniqBy(R.flatten(entries), (x) => x.toString());;
+
+    const deadZones = R.map( entries, ([x,y]) => [ x, x.manhattanDistance(y) ] );
+
+    for ( let x =0; x <= max; x++ ) {
+        for ( let y =0; y <= max; y++ ) {
+            if( nonGrata.some( p => p.x===x && p.y===y ) ) continue;
+
+            const v = V(x,y);
+            if( deadZones.some(
+                d => d[0].manhattanDistance( v ) <= d[1]
+            ) ) continue;
+
+            return x * 4000000 + y;
+        }
+    }
+}
+
+export default findBeacon(4000000);

2022/15/test.js

@@ -2,7 +2,7 @@ import { test, expect, describe } from "vitest";
 
 import { expectSolution } from "../01/main.js";
 import part1, { sample, puzzleInput, unbeaconAtLine } from "./part1.js";
-import part2 from "./part2.js";
+import part2, { findBeacon } from "./part2.js";
 
 describe("part 1", () => {
     test('readInput', () => {
@@ -19,7 +19,10 @@ describe("part 1", () => {
 });
 
 describe("part 2", () => {
-    test.todo("solution", () => {
+    test('sample', () => {
+        expect(findBeacon(20)(sample)).toEqual(56000011);
+    });
+    test.only("solution", () => {
         expectSolution(part2(puzzleInput)).toEqual("TODO");
     });
 });