LeetCode: Roman to Integer

看了别人答案

class Solution {
public:
    int romanToInt(string s) {
        // Start typing your C/C++ solution below
        // DO NOT write int main() function
        map<char, int> S;
        S['I'] = 1;
        S['V'] = 5;
        S['X'] = 10;
        S['L'] = 50;
        S['C'] = 100;
        S['D'] = 500;
        S['M'] = 1000;
        int ret = 0;
        for (int i = 0; i < s.size(); i++) ret += (i>0 && S[s[i]] > S[s[i-1]])? S[s[i]]-2*S[s[i-1]] : S[s[i]];
        return ret;
    }
};

 C#

public class Solution {
    public int RomanToInt(string s) {
        Dictionary<char, int> S = new Dictionary<char, int>();
        S.Add('I', 1); S.Add('V', 5); S.Add('X', 10); S.Add('L', 50);
        S.Add('C', 100); S.Add('D', 500); S.Add('M', 1000);
        int ans = 0;
        for (int i = 0; i < s.Length; i++) {
            ans += (i > 0 && S[s[i]] > S[s[i-1]])? S[s[i]]-2*S[s[i-1]] : S[s[i]];
        }
        return ans;
    }
}