Solve 2025-12, lol

2025/12/index.ts

@@ -0,0 +1,24 @@
+import { sumBy } from '../../utils/array.ts';
+
+export function solveFirst(input: string): number {
+  const rawShapes = input.split('\n\n');
+  const regions = rawShapes
+    .pop()!
+    .split('\n')
+    .map((row) => {
+      const [size, count] = row.split(': ');
+      const [wide, long] = size.split('x').map(Number);
+
+      return { wide, long, count: count.split(' ').map(Number) };
+    });
+  const shapes = rawShapes.map((s) => s.split('\n').slice(1));
+  const shapeWeight = shapes.map((s) =>
+    sumBy(s, (r) => [...r.matchAll(/#/g)].length)
+  );
+
+  // works for the actual data, not for testing lmao
+  const possible = regions.filter(
+    (r) => r.long * r.wide >= sumBy(r.count, (e, i) => e * shapeWeight[i])
+  );
+  return possible.length;
+}