Coderbyte - Array Addition

main.js

function ArrayAddition(arr) { 
  // calculate the largest possible number
  var startArr = arr.sort(function(a,b){return b-a});
  var largest = startArr.shift();

  // return true if the current total plus any number is
  // the largest option
  var checker = function(curArr, curTotal){
    
    // Go through each item in the current set
    for(var i = 0; i < curArr.length; i++){
      var newTotal = curTotal + curArr[i];
      
      // if this item plus the current running total adds
      // up to the largest number, this is considered successful
      if(newTotal === largest){
        return true;
      } else {
        // if they don't match yet, let's try the next level down
        // clone the array...
        var temp = curArr.slice();
        
        // remove the current item in the main loop
        temp.splice(i, 1);
        
        // run checker again. If it comes back as true,
        // quit out of this instance too
        if(checker(temp, newTotal)){
          return true;
        }
      }
    }
    
    // if we get this far, just give back false
    return false;
  }
  
  return checker(startArr, 0); 
}