RomanToInteger.cpp

https://leetcode.com/problems/roman-to-integer/submissions/1211846513/

class Solution {
public:
    int romanToInt(string s) {
        int sum = 0 , index = 0;

        while(index<s.size()-1)
        {
            if(num(s[index])<num(s[index+1]))
            {
                sum-=num(s[index]);
            }
            else
            {
                sum+=num(s[index]);
            }
            index++;
        }
        sum+=num(s[s.size()-1]);
        return sum;
    }
    int num(char c)
    {
        if(c == 'I')
        {
            return 1;
        }
        else if(c == 'V')
        {
            return 5;
        }
        else if(c == 'X')
        {
            return 10;
        }
        else if(c == 'L')
        {
            return 50;
        }
        else if(c == 'C')
        {
            return 100;
        }
        else if(c == 'D')
        {
            return 500;
        }
        else
        {
            return 1000;
        }
    }
};