feat(js): add solutions for 2024 day 2

js/src/2024/02/index.js

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+import { solution } from '../../utils/index.js';
+
+const parse = (input) =>
+  input
+    .trim()
+    .split('\n')
+    .map((line) => line.split(' ').map(Number));
+
+const isSafe = (report) => {
+  let sign;
+  for (let i = 0; i < report.length - 1; ++i) {
+    const current = report[i];
+    const next = report[i + 1];
+
+    const diff = current - next;
+    const diffabs = Math.abs(diff);
+    if (diff === 0) return false;
+    if (diffabs < 1 || diffabs > 3) return false;
+
+    const diffsign = Math.sign(diff);
+    if (sign && diffsign !== sign) return false;
+    sign = diffsign;
+  }
+  return true;
+};
+
+const isSafeWithRemoval = (report) => {
+  const variations = report.map((level, index) => report.slice(0, index).concat(report.slice(index + 1)));
+  return variations.some(isSafe);
+};
+
+export const partOne = solution((input) => {
+  const reports = parse(input);
+  return reports.filter(isSafe).length;
+});
+
+export const partTwo = solution((input) => {
+  const reports = parse(input);
+  return reports.filter(isSafeWithRemoval).length;
+});

puzzles/2024/02/examples.yaml

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+part-one:
+  - input: &example1 |
+      7 6 4 2 1
+      1 2 7 8 9
+      9 7 6 2 1
+      1 3 2 4 5
+      8 6 4 4 1
+      1 3 6 7 9
+    answer: 2
+
+part-two:
+  - input: *example1
+    answer: 4