Solutions to BLITZ problem statements

getIndicesOf.js

/** 
 *Simpler solution using for loop; without using any array.indexOf()
*/

Array.prototype.getIndicesOf  = function(item){
  var indices = [];
  
  for(var i=0; i < this.length; i++){
    if(this[i] === item){
      indices.push(i);
    }
  }
  
  return indices;
};

map-polyfill.js

function userMap(callback){
  var THIS, Arr, index;
  
  if(!this){
    throw new TypeError('This is null or not defined');
  }
  
  var oThis = Object(this);
  var len = oThis.length >>> 0;
  
  if(typeof callback !== 'function'){
    throw new TypeError(callback +' is not a function');
  }
  
  if(arguments.length > 1){
    THIS = arguments[1];
  }
  
  Arr = new Array(len);
  index=0;
  
  while (index < len) {

      var currValue, mappedValue;

      if (index in oThis) {
        currValue = oThis[index];
        mappedValue = callback.call(THIS, currValue, index, oThis);

        Arr[index] = mappedValue;
      }
      
      index++;
    }

    return Arr;
}

if(!Array.prototype.map){
  Array.prototype.userMap = userMap;
}

sum-of-numbers.js

function getSum(num1){
  if(arguments.length > 1){
    var sumOfNums = 0;
    for(var i=0; i<arguments.length; i++){
      sumOfNums+=arguments[i];
    }
    
    return sumOfNums;
  }else{
    return function(num2){
      return num1+num2;
    }
  }
}