day 6 complete!

day06/js/day06b.js

@@ -0,0 +1,81 @@
+import { promises as fsPromises } from "node:fs";
+
+async function asyncReadFile(filename) {
+    try {
+        const contents = await fsPromises.readFile(filename, "utf-8");
+
+        const arr = contents.split(/\r?\n/);
+
+        return arr;
+    } catch (err) {
+        console.error(err);
+    }
+}
+
+const findDividers = (rows) => {
+    let spaceIndexes = [];
+    rows.forEach((row, rowIndex) => {
+        if (row == "") return;
+        if (rowIndex === 0) {
+            Array.from(row).forEach((theChar, charIndex) => {
+                if (theChar === " ") spaceIndexes.push(charIndex);
+            });
+            return;
+        }
+        const rowArray = Array.from(row);
+        spaceIndexes = spaceIndexes.filter(
+            (spaceIndex) => rowArray[spaceIndex] === " "
+        );
+    });
+    return spaceIndexes;
+};
+
+const calculateValues = (operands, operation) => {
+    if (operation === "+")
+        return operands.reduce((acc, curr) => acc + curr * 1, 0);
+    else if (operation === "*")
+        return operands.reduce((acc, curr) => acc * curr, 1);
+};
+
+/*
+const data = `
+123 328  51 64 
+ 45 64  387 23 
+  6 98  215 314
+*   +   *   +  
+`
+    .trim()
+    .split("\n");
+*/
+
+const data = await asyncReadFile("../input.txt");
+
+let total = 0;
+
+const dividers = findDividers(data);
+
+let newOperands = [];
+let operation = "";
+
+for (let c = data[0].length - 1; c >= 0; c--) {
+    if (dividers.includes(c) || c === -1) {
+        const result = calculateValues(newOperands, operation);
+        total += result;
+        console.log(`> result: ${result}`);
+        operation = "";
+        newOperands = [];
+    }
+
+    let newOperandParts = [];
+    data.forEach((row) => {
+        const charArray = Array.from(row);
+        if (/\d+/.test(charArray[c])) newOperandParts.push(charArray[c]);
+        else if (["+", "*"].includes(charArray[c])) operation = charArray[c];
+    });
+    if (newOperandParts.join("") !== "")
+        newOperands.push(newOperandParts.join(""));
+}
+const result = calculateValues(newOperands, operation);
+total += result;
+
+console.log(`>> total: ${total}`);