Custom array reduce function

by Saksham Malhotra

JavaScript

Array.prototype.myReduce = function(fn, acc) {
	let index = 0;
	if(acc == undefined){
		index = 1;
		acc = this[0];
    }

  for(let index = 0; index<this.length; index++) {
  	acc = fn(this[index], acc);
  }
return acc;
}

([11,22,33]).myReduce((acc, val) => (acc + val), 0);