6 lines
230 B
JavaScript
6 lines
230 B
JavaScript
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export default function(ring) {
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var i = 0, n = ring.length, area = ring[n - 1][1] * ring[0][0] - ring[n - 1][0] * ring[0][1];
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while (++i < n) area += ring[i - 1][1] * ring[i][0] - ring[i - 1][0] * ring[i][1];
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return area;
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}
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