Nodejs Array Quick Sort quickSort(comparator)

Method Source Code

// Quicksort/*from w  w  w . ja  v  a 2  s  .  c o m*/
Array.prototype.quickSort = function (comparator) {
  if (typeof comparator !== "function") {
    comparator = function (x, y) {
      if (x === y) {
        return 0;
      } else if (x < y) {
        return -1;
      } else {
        return 1;
      }
    };
  }

  if (this.length < 2) {
    return this;
  }

  const pivot = this[0];
  const left = [];
  const right = [];

  for (let i = 1; i < this.length; i++) {
    if (comparator == undefined) {
      if (this[i] < pivot) {
        left.push(this[i]);
      } else {
        right.push(this[i]);
      }
    } else {
      if (comparator(this[i], pivot) < 0) {
        left.push(this[i]);
      } else {
        right.push(this[i]);
      }
    }
  }

  const lsort = left.quickSort(comparator);
  lsort.push(pivot);
  const rsort = right.quickSort(comparator);
  const sorted = lsort.concat(rsort);
  return sorted;
};

Related

1. quickSort()

   Array.prototype.quickSort = function() {
     var len = this.length
     if(len > 1) {
       var pivot = this[0]
       var left = []
       var right = []
       for(var i = 1; i < len; i++) {
         if(this[i] < pivot) {
           left.push(this[i])
   ...
   

2. quickSort()

   Array.prototype.quickSort = function() {
     var len = this.length;
     if (len <= 1) {
       return this.slice(0);
     var left = [];
     var right = [];
     var mid = [this[0]];
     for (var i = 1; i < len; i++) {
   ...
   

3. quickSort()

   Array.prototype.quickSort = function () {
     if (this.length < 2) {
       return this;
     let pivot = this[0];
     let left = [];
     let right = [];
     for (var i = 1; i < this.length; i++) {
       if (this[i] < pivot) {
   ...
   

4. quickSort()

   Array.prototype.quickSort = function()
     if (this.length === 0) {
       return [];
     var left = [];
     var right = [];
     var pivot = this[0];
     for (var i = 1; i < this.length; i++) {
   ...
   

5. quickSort()

   Array.prototype.quickSort = function () {
       if (this.length <= 1) {
           return this;
       var pointIndex = Math.floor(this.length / 2);
       var pointValue = this.splice(pointIndex, 1);
       var centerValue = pointValue[0];
       var left = [];
       var right = [];
   ...
   

6. quickSort(start, len)

   Array.prototype.quickSort = function(start, len) {
     if (typeof len === "undefined") {
       len = this.length;
     if (len < 2) {
       return this;
   };
   Array.prototype.swap = function (idx1, idx2) {
   ...
   

7. quick_sort()

   Array.prototype.quick_sort = function () {
       if (this.length < 2) { return this; }
       var pivot = this[Math.round(this.length / 2)];
       return this.filter(x => x <  pivot)
                  .quick_sort()
                  .concat(this.filter(x => x == pivot))
                  .concat(this.filter(x => x >  pivot).quick_sort());
   };
   

8. quick_sort()

   Array.prototype.quick_sort = function () {
       if (this.length < 2) { return this; }
       var pivot = this[Math.round(this.length / 2)];
       return this.filter(x => x < pivot)
                  .quick_sort()
                  .concat(this.filter(x => x === pivot))
                  .concat(this.filter(x => x > pivot).quick_sort());
   };
   

9. quick_sort()

   Array.prototype.quick_sort = function ()
       if (this.length <= 1)
           return this;
       var pivot = this[Math.round(this.length / 2)];
       return this.filter(function (x) { return x <  pivot }).quick_sort().concat(
              this.filter(function (x) { return x == pivot })).concat(
              this.filter(function (x) { return x >  pivot }).quick_sort());