71 lines
1.6 KiB
JavaScript
71 lines
1.6 KiB
JavaScript
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(function (exports) {
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'use strict';
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var quicksort = (function () {
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function charAt(str, i) {
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return (i < str.length) ? str.charCodeAt(i) : -1;
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}
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function swap(arr, i, j) {
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var temp = arr[j];
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arr[j] = arr[i];
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arr[i] = temp;
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}
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function quicksort(arr, lo, hi, d) {
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if (lo >= hi) {
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return;
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}
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var lowPointer = lo;
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var highPointer = hi;
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var p = charAt(arr[lo], d);
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var i = lo + 1;
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var current;
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while (i <= highPointer) {
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current = charAt(arr[i], d);
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if (current < p) {
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swap(arr, i, lowPointer);
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lowPointer += 1;
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} else if (current > p) {
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swap(arr, i, highPointer);
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highPointer -= 1;
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i += 1;
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} else {
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i += 1;
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}
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}
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quicksort(arr, lo, lowPointer - 1, d);
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if (p >= 0) {
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quicksort(arr, lowPointer, highPointer, d + 1);
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}
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quicksort(arr, highPointer + 1, hi, d);
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}
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/**
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* Effective inplace string sorting algorithm.
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* Algorithm is NOT stable.
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*
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* @example
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*
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* var sort = require('path-to-algorithms/src/sorting'+
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* '/3-way-string-quicksort').quicksort;
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* console.log(sort(['bb', 'aa', 'cc'])); // [ 'aa', 'bb', 'cc' ]
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*
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* @public
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* @module sorting/3-way-string-quicksort
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* @param arr {Array} array which should be sorted.
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* @return {Array} Sorted array.
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*/
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return function sort(arr) {
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quicksort(arr, 0, arr.length - 1, 0);
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return arr;
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};
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}());
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exports.quicksort = quicksort;
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})(typeof window === 'undefined' ? module.exports : window);
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