solved day 10

Author: shahata

src/2025/day10.js

@@ -0,0 +1,89 @@
+function parse(input) {
+  let machines = input.split("\n").map(line => {
+    let [indicator, ...buttons] = line.split(" ");
+    let joltage = buttons.pop();
+    indicator = indicator
+      .slice(1, -1)
+      .split("")
+      .map((x, i) => (x === "#" ? i : null))
+      .filter(x => x !== null);
+    buttons = buttons.map(button => {
+      button = button
+        .slice(1, -1)
+        .split(",")
+        .map(x => parseInt(x, 10));
+      return new Set(button);
+    });
+    joltage = joltage
+      .slice(1, -1)
+      .split(",")
+      .map(x => parseInt(x, 10));
+    return { indicator: new Set(indicator), buttons: buttons, joltage };
+  });
+  return machines;
+}
+
+function minimumPresses(machine) {
+  let { indicator, buttons } = machine;
+  let queue = [];
+  let visited = new Set();
+  buttons.forEach(button => {
+    queue.push({ pressed: 1, state: button });
+  });
+  while (queue.length > 0) {
+    let { pressed, state } = queue.shift();
+    let stateKey = Array.from(state)
+      .sort((a, b) => a - b)
+      .join(",");
+    if (visited.has(stateKey)) continue;
+    visited.add(stateKey);
+    if (indicator.symmetricDifference(state).size === 0) {
+      return pressed;
+    }
+    buttons.forEach(button => {
+      queue.push({
+        pressed: pressed + 1,
+        state: button.symmetricDifference(state),
+      });
+    });
+  }
+}
+
+function minimumPresses2(machine) {
+  let { buttons, joltage } = machine;
+  let queue = [];
+  let visited = new Set();
+  queue.push({ pressed: 0, state: [...joltage], pushes: [] });
+  while (queue.length > 0) {
+    let { pressed, state, pushes } = queue.shift();
+    let stateKey = state.join(",");
+    if (visited.has(stateKey)) continue;
+    visited.add(stateKey);
+    if (state.every(x => x === 0)) return pressed;
+    if (state.some(x => x < 0)) continue;
+    for (let i = 0; i < buttons.length; i++) {
+      let button = buttons[i];
+      let next = [...state];
+      button.forEach(pos => next[pos]--);
+      queue.push({
+        pressed: pressed + 1,
+        state: next,
+        pushes: pushes.concat(i),
+      });
+    }
+  }
+}
+
+export function part1(input) {
+  let machines = parse(input);
+  let result = 0;
+  machines.forEach(machine => (result += minimumPresses(machine)));
+  return result;
+}
+
+export function part2(input) {
+  let machines = parse(input);
+  let result = 0;
+  machines.forEach(machine => (result += minimumPresses2(machine)));
+  return result;
+}

src/2025/day10.test.js

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+import { part1, part2 } from "./day10.js";
+import { describe, test, expect } from "vitest";
+import readInput from "../utils/read-input.js";
+
+let input = readInput(import.meta.url);
+
+describe("day10 2025", () => {
+  describe("part1", () => {
+    test("it should work for part 1 examples", () => {
+      expect(
+        part1(
+          [
+            "[.##.] (3) (1,3) (2) (2,3) (0,2) (0,1) {3,5,4,7}",
+            "[...#.] (0,2,3,4) (2,3) (0,4) (0,1,2) (1,2,3,4) {7,5,12,7,2}",
+            "[.###.#] (0,1,2,3,4) (0,3,4) (0,1,2,4,5) (1,2) {10,11,11,5,10,5}",
+          ].join("\n"),
+        ),
+      ).toEqual(7);
+    });
+
+    test("it should work for part 1 input", () => {
+      expect(part1(input)).toEqual(409);
+    });
+  });
+
+  describe("part2", () => {
+    test("it should work for part 2 examples", () => {
+      expect(
+        part2(
+          [
+            "[.##.] (3) (1,3) (2) (2,3) (0,2) (0,1) {3,5,4,7}",
+            "[...#.] (0,2,3,4) (2,3) (0,4) (0,1,2) (1,2,3,4) {7,5,12,7,2}",
+            "[.###.#] (0,1,2,3,4) (0,3,4) (0,1,2,4,5) (1,2) {10,11,11,5,10,5}",
+          ].join("\n"),
+        ),
+      ).toEqual(33);
+    });
+
+    test.skip("it should work for part 2 input", () => {
+      expect(part2(input)).toEqual(0); // solved with z3, will implement in code later
+    });
+  });
+});