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diff --git a/‎day4/index.js
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+38Lines changed: 38 additions & 0 deletions b/‎day4/index.js
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+38Lines changed: 38 additions & 0 deletions
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+import { isNumeric } from "../helper.js";
+
+export const part1 = ({ input }) => {
+    let result = 0;
+    input.forEach((row) => {
+        const { have, winning } = getNumbers({ row });
+        const matches = winning.filter((n) => have.includes(n));
+        result += matches.length > 0 ? Math.pow(2, matches.length - 1) : 0;
+    });
+    return result;
+};
+
+export const part2 = ({ input }) => {
+    let result = 0;
+    let cards = Array(input.length).fill(1);
+
+    for (let i = 0; i < input.length; i++) {
+        const { have, winning } = getNumbers({ row: input[i] });
+        const matches = winning.filter((n) => have.includes(n));
+
+        if (matches.length > 0) {
+            for (let j = 1; j <= matches.length; j++) {
+                if (cards[i + j]) cards[i + j] += cards[i];
+            }
+        }
+    }
+    result = cards.reduce((a, b) => a + b, 0);
+
+    return result;
+};
+
+const getNumbers = ({ row }) => {
+    const split = row.split(": ");
+    const numbers = split[1].split(" | ");
+    const winning = numbers[0].split(" ").filter((n) => isNumeric(n));
+    const have = numbers[1].split(" ").filter((n) => isNumeric(n));
+    return { winning, have };
+};