aocd1

2023/1.js

@@ -0,0 +1,85 @@
+const input = require('fs').readFileSync('1.input').toString().split('\n').filter(Boolean);
+
+const lookForFirstDigit = (line) => {
+    for (let i = 0; i < line.length; i++) {
+        const digit = parseInt(line[i]);
+        if (!isNaN(digit)) {
+            return [digit, i];
+        }
+    }
+}
+
+const lookForLastDigit = (line) => {
+    for (let i = line.length - 1; i >= 0; i--) {
+        const digit = parseInt(line[i]);
+        if (!isNaN(digit)) {
+            return [digit, i];
+        }
+    }
+}
+
+const part1 = () => {
+    return input.reduce((acc, line) => {
+        const first = lookForFirstDigit(line)[0];
+        const last = lookForLastDigit(line)[0];
+        const calibrated = first + "" + last;
+        return acc + parseInt(calibrated);
+    }, 0);
+}
+
+
+const words = ["one", "two", "three", "four", "five", "six", "seven", "eight", "nine"];
+const lookForFirstDigitWord = (line) => {
+    let smallestIndex = 100000;
+    let smallestIndexWord = "";
+    for (const word of words) {
+        const index = line.indexOf(word);
+        if (index >= 0) {
+            if (index < smallestIndex) {
+                smallestIndex = index;
+                smallestIndexWord = word;
+            }
+        }
+    }
+    if (smallestIndexWord === "") {
+        return [0, 10000];
+    }
+    return [words.indexOf(smallestIndexWord) + 1, smallestIndex];
+}
+
+const lookForLastDigitWord = (line) => {
+    let biggestIndex = -1;
+    let biggestIndexWord = "";
+    for (const word of words) {
+        const index = line.indexOf(word);
+        if (index >= 0) {
+            if (index > biggestIndex) {
+                biggestIndex = index;
+                biggestIndexWord = word;
+            }
+        }
+    }
+    if (biggestIndexWord === "") {
+        return [0, -1];
+    }
+    return [words.indexOf(biggestIndexWord) + 1, biggestIndex];
+}
+
+const part2 = () => {
+    return input.reduce((acc, line) => {
+        const firstDigit = lookForFirstDigit(line);
+        const firstWord = lookForFirstDigitWord(line);
+        const first = firstDigit[1] < firstWord[1] ? firstDigit[0] : firstWord[0];
+
+        const lastDigit = lookForLastDigit(line);
+        const lastWord = lookForLastDigitWord(line);
+        const last = lastDigit[1] > lastWord[1] ? lastDigit[0] : lastWord[0];
+
+        const calibrated = first + "" + last;
+        return acc + parseInt(calibrated);
+    }, 0);
+}
+
+console.log("Part 1: " + part1());
+console.log("Part 2: " + part2());
+