Solutions for day 3

03/code.js

@@ -0,0 +1,59 @@
+const fs = require('fs');
+
+const inputArray = fs.readFileSync('input.txt').toString().split("\n");
+
+// Part One
+let totalPriority = 0;
+
+for (i in inputArray) {
+  const contents = (inputArray[i]);
+  const intersection = getIntersection(contents);
+  const priority = getPriority(intersection);
+  totalPriority += priority;
+}
+
+console.log(totalPriority);
+
+
+// Part Two
+totalPriority = 0;
+let group = [];
+
+for (i in inputArray) {
+  const contents = (inputArray[i]);
+  group.push(contents.split(""));
+  if (group.length === 3) {
+    const badge = getBadge(group);
+    const priority = getPriority(badge);
+    totalPriority += priority;
+    group = [];
+  }
+}
+
+console.log(totalPriority);
+
+// functions
+
+function getBadge(arrs) {
+  let badge = arrs[0];
+  for(let i = 1; i < arrs.length; i++){
+    badge = intersection(badge, arrs[i]);
+  };
+  return badge[0];
+}
+
+function getIntersection(contents) {
+  const length = contents.length;
+  const first = contents.substring(0, length / 2).split("");
+  const second = contents.substring(length / 2).split("");
+  return intersection(first, second)[0];
+}
+
+function getPriority(char) {
+  const characters = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
+  return characters.indexOf(char) + 1;
+}
+
+function intersection(first, second) {
+  return first.filter(x => second.includes(x));
+};