addTwoNumbers

 var addTwoNumbers = function(l1, l2) {

    var _l1 = "", _l2 = "", answer = 0, answerArr = []

    for(var i = l1.length-1; i >= 0; i--){

        _l1 = _l1 + l1[i]   

    }

  for(var i = l2.length-1; i >= 0; i--){

        _l2 = _l2 + l2[i]   

    }

    answer = parseInt(_l1) + parseInt(_l2)

  for(var i = 0; i < answer.toString().length; i++){

    answerArr.push(parseInt(answer.toString()[i]))

  } 

  

  return answerArr.reverse()

    

};

console.log(addTwoNumbers([2,4,3], [5,6,4]))