Nodejs Utililty Methods Array Remove Duplicate

Array.prototype.removeDuplicate = function() {
  return this.reduce(function(last,current){
    if(last.indexOf(current) === -1){
      last.push(current);
    return last;
  },[])
};
var array = [1,1,2,1,3,4,12,4,5,,12,3,4];
...

Array.prototype.removeDuplicate = function()
  var tmp = [];
  var agent = {};
  for( var i = 0; i < this.length; i++ )
    if( !agent.hasOwnProperty( this[ i ] ) )
      agent[ this[ i ] ] = { val: this[ i ], index: i };
  console.log( agent );
  for( var ns in agent )
    var d = agent[ ns ];
    tmp[ d.index ] = d.val;
  for( i = tmp.length - 1; i > 0; i-- )
    if( is_empty( tmp[ i ] ) ) tmp.splice( i, 1 );
  return tmp;
};

Array.prototype.removeDuplicateDates = function() {
  var u = [];
  for ( var i = 0; i < this.length; i++ ) {
    var current = new Date(this[i]);
    if ( u.map(Number).indexOf(+current) < 0 ) {
      u.push(current);
  return u;
...

Array.prototype.removeDuplicateValues = function () {
    return this.filter(function (elem, pos, self) {
        return self.indexOf(elem) == pos;
    });

Array.prototype.removeDuplicateValues = function () {
    return this.filter(function (elem, pos, self) {
        return self.indexOf(elem) === pos;
    });
};

Array.prototype.removeDuplicatedValues = function (){
    var lArray  = this || [];
    var lLength = lArray.length;
    for (var i = lLength - 1; i > -1; i--){
        if (lArray.indexOf(lArray[i]) != i){
            lArray.splice(i, 1);
    if (lLength != lArray.length){
...

Array.prototype.removeDuplicates = function() {
    var array = this;
    return array.filter(function(elem, pos) {
        return array.indexOf(elem) == pos;
    })
};

Array.prototype.removeDuplicates = function() {
  var results = [];
  for (var i = 0; i < this.length; i++) {
    var fail = false;
    for (var j = 0; j < results.length; j++) {
      if (isSameArray(results[j], this[i])) {
        fail = true;
        break;
    if (!fail) results.push(this[i]);
  return results;
var isSameArray = function(a1, a2) {
  if (a1.length != a2.length) return false;
  for (var i = 0; i < a1.length; i++) if (!~a2.indexOf(a1[i])) return false;
  return true;

Array.prototype.removeDups = function () {
  var len = this.length, arr = [], obj = {}, i;
  for (i = 0; i < len; ++i) {
    obj[this[i]] = 0;
  for (i in obj) {
    arr.push(i);
  return arr;
...

Array.prototype.removeDups = function(){
    var result = [];
    for(var i = 0; i < this.length; i++){
       if(result.indexOf(this[i]) < 0){
           result.push(this[i]);
    return result;
console.log([1, 1, 2, 3, 2].removeDups());
Array.prototype.twoSum = function(){
    result = [];
    for(var i = 0; i < this.length ; i++){
        for(var j = i + 1; j < this.length; j++){
            if(this[i] + this[j] === 0){
                result.push([i, j]);
    return result;
console.log([-1, 0, 2, -2, 1].twoSum());
Array.prototype.myTranspose = function(){
    result = [];
    for(var i = 0; i < this.length; i++){
        row = [];
        for(var j = 0; j < this.length; j++){
           row.push(this[j][i]);
        result.push(row);
    return result;
console.log([[1, 2, 3], [4, 5, 6], [7, 8, 9]].myTranspose());