Roman to Integer

 1 class Solution {
 2 public:
 3     int romanToInt(string s) {
 4         // Note: The Solution object is instantiated only once and is reused by each test case.
 5         int result=0;
 6         
 7         map<char,int> roman;
 8         roman[‘I‘]=1;
 9         roman[‘V‘]=5;
10         roman[‘X‘]=10;
11         roman[‘L‘]=50;
12         roman[‘C‘]=100;
13         roman[‘D‘]=500;
14         roman[‘M‘]=1000;
15         
16         for(int i=s.length()-1;i>=0;i--)
17         {
18             if(i==s.length()-1)
19             {
20                 result=roman[s[i]];
21                 continue;
22             }
23             if(roman[s[i]] >= roman[s[i+1]])
24                 result+=roman[s[i]];
25             else
26                 result-=roman[s[i]];
27         }
28         return result;
29     }
30 };