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  function convertToRoman(num) {
    //create object of decimal to roman key/values
    var numConvertor = {
      1000: 'M',
      900: 'CM',
      500: 'D',
      400: 'CD',
      100: 'C',
      90: 'XC',
      50: 'L',
      40: 'XL',
      10: 'X',
      9: 'IX',
      5: 'V',
      4: 'IV',
      1: 'I'

    let myNumString = "";
    //Get the key values from our numConvertor. We will dual-purpose these:
    // First, they define the key for getting values of out numConvertor, and
    // second, they are the value we want to use to reduce num at each step.
    let  keys = Object.keys(numConvertor);
    // We don't get object keys in any order, so let's sort them.
    keys.sort((a, b) => b - a);
    let i = 0;
    // Our loop is not a for loop, as I want to break the loop when either of two
    //  conditions are met:
    //  - Have we reached the max index?
    //  - Has num been reduced to zero?
    // In either of these cases, the loop can stop.
    while(i<keys.length && num >0){
      // Debug - what is num, the current index, the current value,
      //    and the string we're building?
      console.log(num, i, keys[i], numConvertor[keys[i]], myNumString);
      // Check if the current value of num is divisible by the current key value
      if (Math.floor(num / keys[i]) > 0){
        // If it is, how many times?
        let thisManyTimes = Math.floor(num / keys[i]);
        //  We can append that many of the current character to our string.
        myNumString += numConvertor[keys[i]].repeat(thisManyTimes);
        // And we can also reduce num. The reduction is the modulo function -- 
        //   divided by our current key value, what is the remainder?
        num = num % keys[i];
      // Whether it was divisible or not, increment our index. 
    return myNumString;
  console.log("2018 in roman numerals: ",convertToRoman(2018) );