15 lines
407 B
JavaScript
15 lines
407 B
JavaScript
const [XSgetSeed, XSgetNext, XSrand] = (() => {
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const m = 2 ** 32;
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const XSgetSeed = () => Math.floor(Math.random() * (m - 1)) + 1;
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const s = Uint32Array.of(XSgetSeed());
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return [XSgetSeed, XSgetNext, (seed) => XSgetNext(seed) / m];
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}
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function XSgetNext(seed) {
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if (seed !== undefined) s[0] = seed;
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s[0] ^= s[0] << 13;
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s[0] ^= s[0] >>> 17;
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s[0] ^= s[0] << 5;
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return s[0];
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}
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