40 lines
936 B
JavaScript
40 lines
936 B
JavaScript
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'use strict';
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Object.defineProperty(exports, '__esModule', {
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value: true
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});
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exports.default = shuffleArray;
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exports.rngBuilder = void 0;
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var _pureRand = require('pure-rand');
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/**
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* Copyright (c) Meta Platforms, Inc. and affiliates.
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*
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* This source code is licensed under the MIT license found in the
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* LICENSE file in the root directory of this source tree.
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*/
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const rngBuilder = seed => {
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const gen = (0, _pureRand.xoroshiro128plus)(seed);
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return {
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next: (from, to) =>
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(0, _pureRand.unsafeUniformIntDistribution)(from, to, gen)
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};
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};
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// Fisher-Yates shuffle
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// This is performed in-place
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exports.rngBuilder = rngBuilder;
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function shuffleArray(array, random) {
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const length = array.length;
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if (length === 0) {
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return [];
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}
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for (let i = 0; i < length; i++) {
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const n = random.next(i, length - 1);
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const value = array[i];
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array[i] = array[n];
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array[n] = value;
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}
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return array;
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}
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