Integer to Roman

Given a roman numeral, convert it to an integer.

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

 

public class Solution {
    public String intToRoman(int num) {
        Map<Integer, String> map = new HashMap<Integer, String>();
        map.put(1, "I");
        map.put(4, "IV");
        map.put(5, "V");
        map.put(9, "IX");
        map.put(10, "X");
        map.put(40, "XL");
        map.put(50, "L");
        map.put(90, "XC");
        map.put(100, "C");
        map.put(400, "CD");
        map.put(500, "D");
        map.put(900, "CM");
        map.put(1000, "M");
        int nums[] = {1000,900,500,400,100,90,50,40,10,9,5,4,1};
        String res = "";
        for (int i = 0; i < nums.length; i++) {
        	int t = num/nums[i];
        	num = num%nums[i];
        	for (int j = 1; j <= t; j++) {
        		res += map.get(nums[i]);
        	}
        }
        return res;
    }
}