IntegertoRoman.java

IntegertoRoman.java

 public static void main(String[] args) {
        System.out.println(new Solution().romanToInt("MCMXCIV"));
    }


    static class Solution {

        private int getTotal(String s, char c, int index, int size) {
            if (index == size - 1) return -1;
            char cc = s.charAt(index + 1);

            switch (c) {
                case 'I':
                    return cc == 'V' ? 4 : cc == 'X' ? 9 : 1;
                case 'X':
                    return cc == 'L' ? 40 : cc == 'C' ? 90 : 10;
                case 'C':
                    return cc == 'D' ? 400 : cc == 'M' ? 900 : 100;
                default:
                    return 0;
            }
        }

        public int romanToInt(String s) {
            int len = s.length();
            int total = 0;

            for (int i = 0; i < len; i++) {
                char c = s.charAt(i);
                int t;

                switch (c) {
                    case 'I':
                        t = getTotal(s, c, i, len);
                        total += (t == -1 ? 1 : t);
                        if (t != 1) i++;
                        break;
                    case 'V':
                        total += 5;
                        break;
                    case 'X':
                        t = getTotal(s, c, i, len);
                        total += (t == -1 ? 10 : t);
                        if (t != 10) i++;
                        break;
                    case 'L':
                        total += 50;
                        break;
                    case 'C':
                        t = getTotal(s, c, i, len);
                        total += (t == -1 ? 100 : t);
                        if (t != 100) i++;
                        break;
                    case 'D':
                        total += 500;
                        break;
                    case 'M':
                        total += 1000;
                        break;
                    default:
                        break;
                }
            }

            return total;
        }
    }

Answer provided for LeetCode question:
https://leetcode.com/problems/roman-to-integer/description/

"Runtime 4 ms Beats 95.96% Memory 42.3 MB Beats 95.17%"