88 lines
2.3 KiB
JavaScript
88 lines
2.3 KiB
JavaScript
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(function (exports) {
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'use strict';
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/**
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* The quicksort algorithm. It's complexity is O(nlog n).
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*
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* @public
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*/
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var quickSort = (function () {
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function compare(a, b) {
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return a - b;
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}
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/**
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* Swap the places of two elements
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*
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* @private
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* @param {array} array The array which contains the elements
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* @param {number} i The index of the first element
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* @param {number} j The index of the second element
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* @returns {array} array The array with swaped elements
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*/
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function swap(array, i, j) {
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var temp = array[i];
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array[i] = array[j];
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array[j] = temp;
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return array;
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}
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/**
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* Partitions given subarray using Lomuto's partitioning algorithm.
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*
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* @private
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* @param {array} array Input array
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* @param {number} left The start of the subarray
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* @param {number} right The end of the subarray
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*/
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function partition(array, left, right, compare) {
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var cmp = array[right - 1];
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var minEnd = left;
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var maxEnd;
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for (maxEnd = left; maxEnd < right - 1; maxEnd += 1) {
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if (compare(array[maxEnd], cmp) < 0) {
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swap(array, maxEnd, minEnd);
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minEnd += 1;
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}
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}
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swap(array, minEnd, right - 1);
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return minEnd;
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}
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/**
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* Sorts given array.
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*
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* @private
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* @param {array} array Array which should be sorted
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* @param {number} left The start of the subarray which should be handled
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* @param {number} right The end of the subarray which should be handled
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* @returns {array} array Sorted array
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*/
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function quickSort(array, left, right, cmp) {
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if (left < right) {
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var p = partition(array, left, right, cmp);
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quickSort(array, left, p, cmp);
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quickSort(array, p + 1, right, cmp);
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}
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return array;
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}
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/**
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* Calls the quicksort function with it's initial values.
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*
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* @public
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* @param {array} array The input array which should be sorted
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* @returns {array} array Sorted array
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*/
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return function (array, cmp) {
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cmp = cmp || compare;
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return quickSort(array, 0, array.length, cmp);
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};
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}());
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exports.quickSort = quickSort;
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}(typeof exports === 'undefined' ? window : exports));
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