*Integer to Roman

public class Solution {
    public String intToRoman(int num) 
    {
        if(num <= 0) 
        {
            return "";
        }
        int[] nums = {1000, 900, 500, 400, 100, 90, 50, 40, 10, 9, 5, 4, 1};
        String[] symbols = {"M", "CM", "D", "CD", "C", "XC", "L", "XL", "X", "IX", "V", "IV", "I"};
        StringBuilder res = new StringBuilder();
        int digit=0;
        while(num>0)
        {
            int times = num/nums[digit];
            num -= nums[digit]*times;
            for(;times>0;times--)
            {
                res.append(symbols[digit]);
            }
            digit++;
        }
        return res.toString();
    }
}