Nodejs Array Sum sum()

Method Source Code

function range(a, b) {
    return [...Array(b-a).keys()].map(x => x + a);
}

Array.prototype.sum = function() {
    return this.reduce((a, b) => a + b, 0);
}

module.exports = function(n) {
    var sumOfSquares = range(1,101).map(x => x*x).sum();
    var squareOfSum = Math.pow(range(1,101).sum(), 2);
    return squareOfSum - sumOfSquares;
};

Related

1. sum()

   Array.prototype.sum = function(){
     var sum = 0;
     for(var i = 0; i < this.length; i++){
       if(typeof this[i] === "number"){
         sum += this[i];
     return sum;
   var numbers = [1,2,3,4,5];
   console.log(numbers.sum());
   

2. sum()

   var ary1 = new Array(12, 55, 43, 32, 44);
   var ary2 = new Array(12, 33, 1);
   Array.prototype.sum = function() {
       var output = 0;
       for (var i = 0; i < this.length; i++) {
           output += this[i];
       return output;
   };
   ...
   

3. sum()

   Array.prototype.sum = function(){
     for(var i=0,sum=0;i<this.length;sum+=this[i++]);
     return sum;
   Array.prototype.max = function(){
     return Math.max.apply({},this)
   Array.prototype.first = function(){
     return this[0];
   ...
   

4. sum()

   Array.prototype.sum = function () {
     return this.reduce(function(sum, val){ 
       return sum + val
     })
   console.log([1, 2, 3, 4].sum());
   

5. sum()

   Array.prototype.sum = function() {
     return this.reduce((result, element) => result + element, 0);
   };
   

6. sum()

   Array.prototype.sum = function() {
     return this.reduce(function(p, c, i, arr) {
       return p + c;
     });
   };
   var a = [];
   process.stdin.resume();
   process.stdin.setEncoding("utf8");
   process.stdin.on("data", getNum);
   ...
   

7. sum()

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

8. sum()

   Array.prototype.sum = function () {
       var total = 0;
       var i = this.length;
       while (i--) {
           total += this[i];
       return total;
   function isEmpty(obj) {
   ...
   

9. sum()

   Array.prototype.sum = function () {
     return this.reduce((sum, n) => sum + Number(n), 0)