http://www.freecodecamp.com/tylerl-uxai 's solution for Bonfire: Roman Numeral Converter

bonfire-roman-numeral-converter.js

// Bonfire: Roman Numeral Converter
// Author: @tylerl-uxai
// Challenge: http://www.freecodecamp.com/challenges/bonfire-roman-numeral-converter
// Learn to Code at Free Code Camp (www.freecodecamp.com)
// re-wrote by myself with the aid of http://wulkan.me/bonfire-roman-numeral-converter/

function convert(num) {
  var romanNumerals = '',
      decimals = [1000, 900, 500, 400, 100, 90, 50, 40, 10, 9, 5, 4, 1],
      numerals = ['M', 'CM', 'D', 'CD', 'C', 'XC', 'L', 'XL', 'X', 'IX', 'V', 'IV', 'I'];
  
  for (var i= 0; i < decimals.length; i++){
    while ( num >= decimals[i] ) {
      romanNumerals += numerals[i];
      num -= decimals[i];
    }
  }
  return romanNumerals;
}

convert(36);