mirror of
https://github.com/multipleof4/lynchmark.git
synced 2026-01-14 16:47:55 +00:00
21 lines
758 B
JavaScript
21 lines
758 B
JavaScript
const findConvexHull = async (points) => {
|
|
const _ = await import('https://cdn.skypack.dev/lodash');
|
|
const sorted = _.uniqBy(points, p => `${p.x},${p.y}`).sort((a, b) => a.x - b.x || a.y - b.y);
|
|
if (sorted.length < 3) return sorted;
|
|
const cross = (o, a, b) => (a.x - o.x) * (b.y - o.y) - (a.y - o.y) * (b.x - o.x);
|
|
const buildHull = (pts) => {
|
|
const hull = [];
|
|
for (const p of pts) {
|
|
while (hull.length >= 2 && cross(hull[hull.length - 2], hull[hull.length - 1], p) <= 0) hull.pop();
|
|
hull.push(p);
|
|
}
|
|
hull.pop();
|
|
return hull;
|
|
};
|
|
const lower = buildHull(sorted);
|
|
const upper = buildHull(sorted.reverse());
|
|
return lower.concat(upper);
|
|
};
|
|
export default findConvexHull;
|
|
// Generation time: 9.132s
|
|
// Result: PASS
|