July 21, 2019

12. Integer to Roman

Cases:
I V X L C D M
1 5 10 50 100 500 1000

Special cases:
IV IX XL XC CD CM
1 4 40 90 400 900

数位分离: %10 /10
37215

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