You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
88 lines
2.3 KiB
JavaScript
88 lines
2.3 KiB
JavaScript
(function (exports) {
|
|
|
|
'use strict';
|
|
|
|
/**
|
|
* The quicksort algorithm. It's complexity is O(nlog n).
|
|
*
|
|
* @public
|
|
*/
|
|
var quickSort = (function () {
|
|
|
|
function compare(a, b) {
|
|
return a - b;
|
|
}
|
|
|
|
/**
|
|
* Swap the places of two elements
|
|
*
|
|
* @private
|
|
* @param {array} array The array which contains the elements
|
|
* @param {number} i The index of the first element
|
|
* @param {number} j The index of the second element
|
|
* @returns {array} array The array with swaped elements
|
|
*/
|
|
function swap(array, i, j) {
|
|
var temp = array[i];
|
|
array[i] = array[j];
|
|
array[j] = temp;
|
|
return array;
|
|
}
|
|
|
|
/**
|
|
* Partitions given subarray using Lomuto's partitioning algorithm.
|
|
*
|
|
* @private
|
|
* @param {array} array Input array
|
|
* @param {number} left The start of the subarray
|
|
* @param {number} right The end of the subarray
|
|
*/
|
|
function partition(array, left, right, compare) {
|
|
var cmp = array[right - 1];
|
|
var minEnd = left;
|
|
var maxEnd;
|
|
for (maxEnd = left; maxEnd < right - 1; maxEnd += 1) {
|
|
if (compare(array[maxEnd], cmp) < 0) {
|
|
swap(array, maxEnd, minEnd);
|
|
minEnd += 1;
|
|
}
|
|
}
|
|
swap(array, minEnd, right - 1);
|
|
return minEnd;
|
|
}
|
|
|
|
/**
|
|
* Sorts given array.
|
|
*
|
|
* @private
|
|
* @param {array} array Array which should be sorted
|
|
* @param {number} left The start of the subarray which should be handled
|
|
* @param {number} right The end of the subarray which should be handled
|
|
* @returns {array} array Sorted array
|
|
*/
|
|
function quickSort(array, left, right, cmp) {
|
|
if (left < right) {
|
|
var p = partition(array, left, right, cmp);
|
|
quickSort(array, left, p, cmp);
|
|
quickSort(array, p + 1, right, cmp);
|
|
}
|
|
return array;
|
|
}
|
|
|
|
/**
|
|
* Calls the quicksort function with it's initial values.
|
|
*
|
|
* @public
|
|
* @param {array} array The input array which should be sorted
|
|
* @returns {array} array Sorted array
|
|
*/
|
|
return function (array, cmp) {
|
|
cmp = cmp || compare;
|
|
return quickSort(array, 0, array.length, cmp);
|
|
};
|
|
}());
|
|
|
|
exports.quickSort = quickSort;
|
|
|
|
}(typeof exports === 'undefined' ? window : exports));
|