Day02

.nvmrc

@@ -0,0 +1 @@
+v18.20.5

README.md

@@ -6,7 +6,7 @@ my 2024 solutions on ~~glitch: [meowing-holy-carbon](https://meowing-holy-carbon
 
 also on github: [dieseltravis/aoc2024](https://github.com/dieseltravis/aoc2024)
 
-[![Days completed in a row](https://img.shields.io/badge/⭐%20days%20in%20a%20row-01-blueviolet)](https://adventofcode.com/2024/) [![Node.js CI](https://github.com/dieseltravis/aoc2024/actions/workflows/node.js.yml/badge.svg)](https://github.com/dieseltravis/aoc2024/actions/workflows/node.js.yml) [![js-semistandard-style](https://img.shields.io/badge/code%20style-semistandard-brightgreen.svg?logo=javascript)](https://github.com/standard/semistandard)
+[![Days completed in a row](https://img.shields.io/badge/⭐%20days%20in%20a%20row-2-blueviolet)](https://adventofcode.com/2024/) [![Node.js CI](https://github.com/dieseltravis/aoc2024/actions/workflows/node.js.yml/badge.svg)](https://github.com/dieseltravis/aoc2024/actions/workflows/node.js.yml) [![js-semistandard-style](https://img.shields.io/badge/code%20style-semistandard-brightgreen.svg?logo=javascript)](https://github.com/standard/semistandard)
 
 ## solutions:
 Install node `>18.18.x`, `yarn`, and then run `yarn install` and then `yarn start`.

package.json

@@ -1,6 +1,6 @@
 {
   "name": "meowing-holy-carbon",
-  "version": "2024.12.01",
+  "version": "2024.12.02",
   "description": "Travis's Advent of Code 2024",
   "author": "Travis Hardiman",
   "homepage": "https://github.com/dieseltravis/aoc2024/",

public/funs.js

@@ -45,8 +45,95 @@
       }
     },
     day2: {
-      part1: d => d,
-      part2: d => d
+      part1: (data) => {
+        const input = data.trim().split('\n').map(r => r.split(' ').map(Number)).reduce((acc, r) => {
+          let ascending = 0;
+          let descending = 0;
+          const max = r.reduce((diff, c, i) => {
+            if (i > 0) {
+              const fromPrev = r[i - 1] - c;
+              diff = Math.max(diff, Math.abs(fromPrev));
+              const ordering = fromPrev > 0 ? 1 : fromPrev < 0 ? -1 : 0;
+              if (ordering > 0) {
+                ascending++;
+              } else if (ordering < 0) {
+                descending++;
+              }
+            }
+            return diff;
+          }, 0);
+          acc.push({
+            row: r,
+            max,
+            allMoved: (r.length - 1 === ascending + descending),
+            isOrder: (ascending === 0 || descending === 0)
+          });
+          return acc;
+        }, []);
+        console.log(input);
+
+        return input.filter(r => r.max <= 3 && r.allMoved && r.isOrder).length;
+      },
+      part2: (data) => {
+        const input = data.trim().split('\n').map(r => r.split(' ').map(Number)).reduce((acc, r) => {
+          let ascending = 0;
+          let descending = 0;
+          const max = r.reduce((diff, c, i) => {
+            if (i > 0) {
+              const fromPrev = r[i - 1] - c;
+              diff = Math.max(diff, Math.abs(fromPrev));
+              const ordering = fromPrev > 0 ? 1 : fromPrev < 0 ? -1 : 0;
+              if (ordering > 0) {
+                ascending++;
+              } else if (ordering < 0) {
+                descending++;
+              }
+            }
+            return diff;
+          }, 0);
+          acc.push({
+            row: r,
+            max,
+            allMoved: (r.length - 1 === ascending + descending),
+            isOrder: (ascending === 0 || descending === 0)
+          });
+          return acc;
+        }, []);
+        console.log(input);
+
+        const valid = input.filter(r => r.max <= 3 && r.allMoved && r.isOrder).length;
+        const second = input.filter(r => !(r.max <= 3 && r.allMoved && r.isOrder)).reduce((acc, r) => {
+          for (let l = r.row.length; l--;) {
+            const index = l;
+            const chance = r.row.filter((_, i) => i !== index);
+            let ascending = 0;
+            let descending = 0;
+            for (let ll = chance.length; ll--;) {
+              if (ll > 0) {
+                const fromPrev = chance[ll - 1] - chance[ll];
+                if (Math.abs(fromPrev) <= 3) {
+                  const ordering = fromPrev > 0 ? 1 : fromPrev < 0 ? -1 : 0;
+                  if (ordering > 0) {
+                    ascending++;
+                  } else if (ordering < 0) {
+                    descending++;
+                  } else {
+                    break;
+                  }
+                }
+              }
+            }
+            if ((ascending === 0 || descending === 0) && (chance.length - 1 === ascending + descending)) {
+              acc++;
+              console.log(acc);
+              break;
+            }
+          }
+          return acc;
+        }, 0);
+
+        return valid + second;
+      }
     },
     day3: {
       part1: d => d,

views/index.html

@@ -21,8 +21,8 @@ <h1>Travis's Advent of Code 2024</h1>
       <h2>solutions:</h2>
       <ol>
         <li><a href="/day/01">day 01</a></li>
-        <!-- 
         <li><a href="/day/02">day 02</a></li>
+        <!-- 
         <li><a href="/day/03">day 03</a></li>
         <li><a href="/day/04">day 04</a></li>
         <li><a href="/day/05">day 05</a></li>