From 2f7c1f10323a26dea066eecb52b1c3fae746c0f5 Mon Sep 17 00:00:00 2001
From: Piotr Russ <piotr.russ@betvictor.com>
Date: Mon, 14 Dec 2020 12:10:49 +0100
Subject: day14

---
 day14/day14-2.js | 48 ++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 48 insertions(+)
 create mode 100644 day14/day14-2.js

(limited to 'day14/day14-2.js')

diff --git a/day14/day14-2.js b/day14/day14-2.js
new file mode 100644
index 0000000..c9b2f0c
--- /dev/null
+++ b/day14/day14-2.js
@@ -0,0 +1,48 @@
+const data = require('./data')
+const splitted = data
+  .split(/mask = /g)
+  .filter(d => d !== '\n')
+  .map(d => d.split(/\n/g))
+  .map(d => d.map((a, i) => (i > 0 ? a.match(/\d+/g) : a)).filter(a => a))
+  .map(d => d.map((a, i) => (i > 0 ? a.map(b => parseInt(b).toString(2).padStart(36, '0')) : a)))
+
+const allVariations = (str, arr) => {
+  let i = str.indexOf('X');
+
+  if (i < 0) {
+    arr.push(str);
+    return;
+  }
+
+  const splitStr = str.split('');
+  let addZero = splitStr.slice();
+  let addOne = splitStr.slice();
+
+  addZero.splice(i, 1, '0');
+  addOne.splice(i, 1, '1');
+
+  allVariations(addZero.join(''), arr);
+  allVariations(addOne.join(''), arr );
+}
+
+const mem = {}
+splitted.forEach(s => {
+  const mask = s[0]
+  const applyMask = (str) => (
+    str.split('').map((v, i) => (mask[i] === '0' ? v : mask[i])).join('')
+  )
+
+  let variations
+  s.forEach((m, i) => {
+    variations = []
+    if (i > 0) {
+      allVariations(applyMask(m[0]), variations)
+      variations.forEach(a => {
+        mem[parseInt(a, 2)] = parseInt(m[1], 2)
+      })
+    }
+  })
+})
+
+const sum = Object.values(mem).reduce((a, b) => a + b, 0)
+console.log('Answer: ', sum)
-- 
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