2022 - Day 3

2022/03/solution.ts

@@ -0,0 +1,39 @@
+const sample1 = await Deno.readTextFile("sample1.txt");
+const sample2 = await Deno.readTextFile("sample2.txt");
+const input = await Deno.readTextFile("input.txt");
+
+const solvePart1 = (data: string): number =>
+  data
+    .split("\n")
+    .filter(Boolean)
+    .map((line) => [
+      new Set(line.substring(0, line.length / 2).split("")),
+      new Set(line.substring((line.length - 1) / 2 + 1, line.length).split("")),
+    ])
+    .map(([set1, set2]) => [...set1].filter((v) => set2.has(v)).pop())
+    .map((c) => c?.charCodeAt(0)!)
+    .map((c) => c - (c > 96 ? 96 : 64 - 26))
+    .reduce((sum, value) => sum + value, 0);
+
+console.log("Sample1:", solvePart1(sample1));
+console.log("Input", solvePart1(input));
+
+const solvePart2 = (data: string): number =>
+  data
+    .split("\n")
+    .filter(Boolean)
+    .map((line) => new Set(line.split("")))
+    .reduce((result, set, index) => {
+      const resultIndex = Math.floor(index / 3);
+      result[resultIndex] = [...(result[resultIndex] || []), set];
+      return result;
+    }, [] as Set<string>[][])
+    .map(([set1, set2, set3]) =>
+      [...set1].filter((v) => set2.has(v) && set3.has(v)).pop()
+    )
+    .map((c) => c?.charCodeAt(0)!)
+    .map((c) => c - (c > 96 ? 96 : 64 - 26))
+    .reduce((sum, value) => sum + value, 0);
+
+console.log("Sample:", solvePart2(sample2));
+console.log("Input", solvePart2(input));