Solve 2025-05

2025/05/index.ts

@@ -0,0 +1,36 @@
+import type { Coordinate } from '../../utils/coordinates.ts';
+
+function parseRanges(input: string) {
+  return Array.from(
+    input.matchAll(/(\d*)-(\d*)/gm),
+    (m) => [Number(m[1]), Number(m[2])] as Coordinate
+  );
+}
+
+export function solveFirst(input: string): number {
+  const [r, i] = input.split('\n\n');
+
+  const ranges = parseRanges(r);
+
+  const ingredients = i.split('\n').map(Number);
+
+  return ingredients.filter((i) =>
+    ranges.some(([from, to]) => i >= from && i <= to)
+  ).length;
+}
+
+export function solveSecond(input: string): number {
+  const ranges = parseRanges(input).toSorted((a, b) => a[0] - b[0]);
+
+  let total = 0;
+
+  ranges.reduce((lastEnd, curr) => {
+    if (curr[1] <= lastEnd) {
+      return lastEnd;
+    }
+    total += curr[1] - Math.max(lastEnd + 1, curr[0]) + 1;
+    return curr[1];
+  }, 0);
+
+  return total;
+}