leetcode[12]Integer to Roman

Given an integer, convert it to a roman numeral.

Input is guaranteed to be within the range from 1 to 3999.

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