day 04 part 1 finished

2023/day04/index.js

@@ -0,0 +1,25 @@
+import fs from "node:fs";
+const lines = fs.readFileSync("input.txt", "utf-8").split("\n");
+let result = 0;
+
+lines.forEach((line) => {
+    result += countCardPoints(line);
+});
+
+console.log(result);
+
+function countCardPoints(line) {
+    const lists = line.split(":")[1].trim().split("|");
+
+    const [winningNumbers, myNumbers] = lists.map(
+        (item) => item.match(/\d+/g)?.map(Number) || []
+    );
+
+    const commonItems = myNumbers.filter((item) => winningNumbers.includes(item));
+
+    let output = 0;
+    if (commonItems.length > 0) {
+        output += 2 ** (commonItems.length - 1);
+    }
+    return output;
+}