mirror of
https://github.com/lynchmarkHQ/lynchmark.com.git
synced 2026-10-08 21:35:23 +00:00
33 lines
885 B
JavaScript
33 lines
885 B
JavaScript
async function findConvexHull(points) {
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const _ = (await import("https://cdn.jsdelivr.net/npm/lodash-es/lodash.js")).default;
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const unique = _.uniqWith(points, _.isEqual);
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const sorted = _.sortBy(unique, ["x", "y"]);
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if (sorted.length <= 1) return sorted;
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const cross = (O, A, B) =>
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(A.x - O.x) * (B.y - O.y) - (A.y - O.y) * (B.x - O.x);
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const lower = [];
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for (const p of sorted) {
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while (lower.length >= 2 && cross(lower[lower.length - 2], lower[lower.length - 1], p) <= 0)
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lower.pop();
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lower.push(p);
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}
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const upper = [];
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for (const p of _.reverse([...sorted])) {
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while (upper.length >= 2 && cross(upper[upper.length - 2], upper[upper.length - 1], p) <= 0)
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upper.pop();
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upper.push(p);
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}
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lower.pop();
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upper.pop();
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return [...lower, ...upper];
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}
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export default findConvexHull;
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// Generation time: 5.094s
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// Result: PASS
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