function convertToRoman(num) {
  //turn num into an arr of nums
  //1st turn num into str, 2nd turn str into arr of chars, 3rd turn each char into num
  var numArr = num.toString().split("").map(Number);
  //reverse array to make pushing the roman numerals easier
  numArr.reverse();
  //create array of roman numerals to push into newArray to be returned
  var ones = ["I", "II", "III", "IV", "V", "VI", "VII", "VIII", "IX"];
  var tens = ["X", "XX", "XXX", "XL", "L", "LX", "LXX", "LXXX", "XC"];
  var hundreds = ["C", "CC", "CCC", "CD", "D", "DC", "DCC", "DCCC", "CM"];
  var thousands = ["M", "MM", "MMM"];

  var newArr = [];//newArr to be returned in place of num
  var digitTracker = 0;//for keeping track of ones place, tens place, etc.

  for (var i = 0; i < numArr.length; i++){
  	if (digitTracker === 0){
      newArr.push(ones[numArr[i] - 1]);
      digitTracker++;//after updating digitTracker, now we can move on to tens place
    } else if (digitTracker == 1){
      newArr.push(tens[numArr[i] - 1]);
      digitTracker++;
    } else if (digitTracker == 2){
      newArr.push(hundreds[numArr[i] - 1]);
      digitTracker++;
    } else if (digitTracker == 3){
      newArr.push(thousands[numArr[i] - 1]);
    }

  }

  var romanNum = newArr.reverse().join("");
  return romanNum;
}

convertToRoman(99);

/*The code below has twice as many lines of code; it works, but the code above
works as well, and has less lines of code*/

/*
function convertToRoman(num) {
  //turn num into an arr of nums
  //1st turn num into str, 2nd turn str into arr of chars, 3rd turn each char into num
  var numArr = num.toString().split("").map(Number);
  var ones = ["I", "II", "III", "IV", "V", "VI", "VII", "VIII", "IX"];
  var tens = ["X", "XX", "XXX", "XL", "L", "LX", "LXX", "LXXX", "XC"];
  var hundreds = ["C", "CC", "CCC", "CD", "D", "DC", "DCC", "DCCC", "CM"];
  var thousands = ["M", "MM", "MMM"];
  var strArr = [];//create new strArr for pushing the roman letters into

  var romanArrCounter = 0;
  var numArrCounter = numArr.length - 1;//only move if number is replaced with roman letter
  var digitTracker = 1;

  while (numArrCounter > -1){
    if (numArr[numArrCounter] == romanArrCounter){
      if (digitTracker == 1){//for one's position
        //if digit !== null (i.e. digit is not 0)
        if (numArr[numArrCounter] !== 0){
          numArr.splice(numArrCounter, 1, ones[romanArrCounter - 1]);
          numArrCounter--;
          romanArrCounter = 0;
          digitTracker++;
        } else {//if digit is 0, just replace it with ""
          numArr.splice(numArrCounter - (numArrCounter + 1), 1, "");
          numArrCounter--;
          romanArrCounter = 0;
          digitTracker++;
        }
      } else if (digitTracker == 2){//for ten's position
        if (numArr[numArrCounter] !== 0){
          numArr.splice(numArrCounter, 1, tens[romanArrCounter - 1]);
          numArrCounter--;
          romanArrCounter = 0;
          digitTracker++;
        } else {
          numArr.splice(numArrCounter - (numArrCounter + 2), 1, "");
          numArrCounter--;
          romanArrCounter = 0;
          digitTracker++;
        }
      } else if (digitTracker == 3){//for hundred's position
        if (numArr[numArrCounter] !== 0){
          numArr.splice(numArrCounter, 1, hundreds[romanArrCounter - 1]);
          numArrCounter--;
          romanArrCounter = 0;
          digitTracker++;
        } else {
          numArr.splice(numArrCounter - (numArrCounter + 3), 1, "");
          numArrCounter--;
          romanArrCounter = 0;
          digitTracker++;
        }
      } else if (digitTracker == 4){//for thousand's position
        if (numArr[numArrCounter] !== 0){
          numArr.splice(numArrCounter, 1, thousands[romanArrCounter - 1]);
          numArrCounter--;
          romanArrCounter = 0;
        } else {
          numArr.splice(numArrCounter - (numArrCounter + 4), 1, "");
          numArrCounter--;
          romanArrCounter = 0;
        }
      }
    } else {
      romanArrCounter++;
    }
  }

  var romanNum = numArr.join("");
  return romanNum;
  //return numArr[numArrCounter];
}

convertToRoman(3999);
*/