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Roman to Integer

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Given a roman numeral, convert it to an integer. ie given string of "LVIII" return 58

class Solution {
    public int romanToInt(String s) {
        Map<Character, Integer> m = new HashMap<>();
        
        m.put('I', 1);
        m.put('V', 5);
        m.put('X', 10);
        m.put('L', 50);
        m.put('C', 100);
        m.put('D', 500);
        m.put('M', 1000);
        
        int ans = 0;
        
        for (int i = 0; i < s.length(); i++) {
            if (i < s.length() - 1 && m.get(s.charAt(i)) < m.get(s.charAt(i + 1))) {
                ans -= m.get(s.charAt(i));
            } else {
                ans += m.get(s.charAt(i));
            }
        }
        
        return ans;
    }
}

Posted by Jamie Meyer 7 months ago

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