http://www.freecodecamp.com/patrickcurl 's solution for Bonfire: Roman Numeral Converter

bonfire-roman-numeral-converter.js

// Bonfire: Roman Numeral Converter
// Author: @patrickcurl
// Challenge: http://www.freecodecamp.com/challenges/bonfire-roman-numeral-converter
// Learn to Code at Free Code Camp (www.freecodecamp.com)

function convert(num) { 
  if(num < 1){ return "";}
  if(num >= 1000){return "M" + convert(num-1000);}
  if(num >= 900){ return "CM" + convert(num-900);}
  if(num >= 500){return "D" + convert(num-500);}
  if(num >= 400){ return "CD" + convert(num-400);}
  if(num >=100){ return "C" + convert(num -100);}
  if(num >=90){ return "XC" + convert(num -90);}
  if(num >= 50){ return "L" + convert(num - 50); }
  if(num >= 40){ return "XL" + convert(num - 40);}
  if(num >= 10){ return "X" + convert(num - 10);}
  if(num >= 9){ return "IX" + convert(num - 9);}
  if(num >= 5){ return "V" + convert(num - 5);}
  if(num >= 4){ return "IV" + convert(num - 4);}
  if(num >= 1){ return "I" + convert(num - 1);}  
}

convert(36);