Roman to interger.cpp

class Solution {
public:
    int romanToInt(string s) {
        int ans = 0;
        unordered_map<char,int>mp{
        {'I',1},{'V',5},{'X',10},{'L',50},{'C',100},{'D',500},{'M',1000}
        };
        for(int i=0;i<s.size();i++)
        {
            if(mp[s[i]]<mp[s[i+1]]) ans = ans-mp[s[i]];
            else ans = ans+mp[s[i]];
        }
        return ans;
        
    }
};