feat(day-3): add first part solution

1 files changed, 36 insertions, 0 deletions

diff --git a/day-3/script.ts b/day-3/script.ts
new file mode 100644
index 0000000..1793e48
--- /dev/null
+++ b/day-3/script.ts
@@ -0,0 +1,36 @@
+import fs from "fs";
+
+const input = fs.readFileSync("./input.txt").toString();
+
+const lineLength = input.split("\n")[0].length;
+
+const chars = input.split("\n").slice(0, -1).join("");
+
+const numbers = Array.from(chars.matchAll(/[\d]+/g)).map((match) => ({
+  number: Number(match[0]),
+  position: {
+    start: match.index || 0,
+    end: (match.index || 0) + match[0].length,
+  },
+}));
+
+const symbols = Array.from(chars.matchAll(/[^\.\d]/g)).map((match) => ({
+  symbol: match[0],
+  position: match.index || 0,
+}));
+
+const result = numbers
+  .filter((number) => {
+    return !!symbols.find(
+      (symbol) =>
+        symbol.position === number.position.start - 1 ||
+        symbol.position === number.position.end ||
+        (symbol.position >= number.position.start - 1 - lineLength &&
+          symbol.position <= number.position.end - lineLength) ||
+        (symbol.position >= number.position.start - 1 + lineLength &&
+          symbol.position <= number.position.end + lineLength),
+    );
+  })
+  .reduce((acc, number) => acc + number.number, 0);
+
+console.log({ result });