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25 lines
902 B
JavaScript
25 lines
902 B
JavaScript
const findConvexHull = async (points) => {
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const _ = await import('https://cdn.jsdelivr.net/npm/lodash@4.17.21/lodash.min.js');
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const pts = _.sortBy(_.uniqWith(points, (a, b) => a.x === b.x && a.y === b.y), ['x', 'y']);
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const n = pts.length;
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if (n <= 2) return pts;
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const cross = (o, a, b) => (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 (let i = 0; i < n; i++) {
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while (lower.length >= 2 && cross(lower[lower.length - 2], lower[lower.length - 1], pts[i]) <= 0)
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lower.pop();
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lower.push(pts[i]);
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}
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const upper = [];
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for (let i = n - 1; i >= 0; i--) {
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while (upper.length >= 2 && cross(upper[upper.length - 2], upper[upper.length - 1], pts[i]) <= 0)
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upper.pop();
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upper.push(pts[i]);
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}
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lower.pop();
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upper.pop();
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return lower.concat(upper);
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};
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export default findConvexHull;
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// Generation time: 21.237s
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// Result: FAIL
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