mirror of
https://github.com/multipleof4/lynchmark.git
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30 lines
917 B
JavaScript
30 lines
917 B
JavaScript
const findConvexHull = async points => {
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const _ = await import('https://unpkg.com/lodash@4.17.21/lodash.js');
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const sorted = _.uniqWith(_.sortBy(points, ['x', 'y']), _.isEqual);
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if (sorted.length <= 2) return sorted;
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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 < sorted.length; i++) {
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while (lower.length >= 2 && cross(lower[lower.length - 2], lower[lower.length - 1], sorted[i]) <= 0) {
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lower.pop();
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}
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lower.push(sorted[i]);
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}
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const upper = [];
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for (let i = sorted.length - 1; i >= 0; i--) {
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while (upper.length >= 2 && cross(upper[upper.length - 2], upper[upper.length - 1], sorted[i]) <= 0) {
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upper.pop();
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}
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upper.push(sorted[i]);
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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: 17.814s
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// Result: FAIL
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