dist-javascript-algorithms-and-data-structures/dist/algorithms/sorting/quick-sort/QuickSort.js

Algorithms and data-structures implemented on JavaScript

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = void 0;

var _Sort = _interopRequireDefault(require("../Sort"));

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

class QuickSort extends _Sort.default {
  /**
   * @param {*[]} originalArray
   * @return {*[]}
   */
  sort(originalArray) {
    // Clone original array to prevent it from modification.
    const array = [...originalArray]; // If array has less than or equal to one elements then it is already sorted.

    if (array.length <= 1) {
      return array;
    } // Init left and right arrays.


    const leftArray = [];
    const rightArray = []; // Take the first element of array as a pivot.

    const pivotElement = array.shift();
    const centerArray = [pivotElement]; // Split all array elements between left, center and right arrays.

    while (array.length) {
      const currentElement = array.shift(); // Call visiting callback.

      this.callbacks.visitingCallback(currentElement);

      if (this.comparator.equal(currentElement, pivotElement)) {
        centerArray.push(currentElement);
      } else if (this.comparator.lessThan(currentElement, pivotElement)) {
        leftArray.push(currentElement);
      } else {
        rightArray.push(currentElement);
      }
    } // Sort left and right arrays.


    const leftArraySorted = this.sort(leftArray);
    const rightArraySorted = this.sort(rightArray); // Let's now join sorted left array with center array and with sorted right array.

    return leftArraySorted.concat(centerArray, rightArraySorted);
  }

}

exports.default = QuickSort;