Use dictionary and divmod

```
def intToRoman(self, num):
"""
:type num: int
:rtype: str
"""
dic = {"M":1000,"CM":900,"D":500,"CD":400,"C":100,"XC":90,"L":50,"XL":40,"X":10,"IX":9,"V":5,"IV":4,"I":1}
dic_keys = sorted(dic.keys(), key=dic.get, reverse=True)
result = ''
for k in dic_keys:
quotient, num = divmod(num, dic[k]) # num = remainder
if quotient != 0:
result += k*quotient
if num == 0:
return result
return result
```