Nodejs Utililty Methods Array Sum

Array.prototype.sum = function () {
  return this.reduce(function(a, b) {
    return a + b;
  });
};
console.log([1, 2, 3].sum());

Array.prototype.sum = function () {
  return this.reduce(function (value, current) {
    return value + current;
  }, 0);
};

Array.prototype.sum = function () {
  return (!this.length) ? 0 : this.reduce((acc, value) => {
    return acc + value;
  });
};

Array.prototype.sum=function(){return this.reduce(function(s,n){return s+n})}
function NumberAddition(str) {
  return str.replace(/[^\d]/g, ' ').split(' ').map(Number).sum();
NumberAddition(readline());

function extend(destination, source) {
    for (var property in source) {
        destination[property] = source[property];
    return destination;
Array.prototype.sum = function() {
    var result = 0;
    for (var i = 0; i < this.length; i++) {
...

Array.prototype.sum = function() {
  var n = 0;
  this.forEach(function(e) {
    n += e;
  });
  return n;
};

Math.TAU = Math.PI * 2;
Array.prototype.sum = function()
  for (var i = 0, L = this.length, sum = 0; i < L; sum += this[i++]);
  return sum;
Array.prototype.product = function()
  for (var i = 0, L = this.length, product = 1; i < L; product =  product * this[i++]);
...

Array.prototype.sum = function(){
  return this.reduce(function(sum, item){
    return sum + item;
  }, 0)
function isInt(n){
    return Number(n) === n && n % 1 === 0;
function isFloat(n){
...

Array.prototype.sum = function() {
  var sum = 0;
  this.forEach(function(k) {
    sum += k;
  });
  return sum;
};

Array.prototype.sum = function()
  if (this.length < 1) {
    return Number.NaN;
  var sum = 0;
  this.forEach(function(a) {
    sum += a;
  });
...