LeetCode: Roman to Integer

13. Roman to Integer

Total Accepted: 77116 Total Submissions: 199727 Difficulty: Easy
Given a roman numeral, convert it to an integer.

Input is guaranteed to be within the range from 1 to 3999.

class Solution {
public:
int romanToInt(string s) {
int map[26];
char romanChar[] = { 'I', 'V', 'X', 'L', 'C', 'D', 'M' };
map['I' - 'A'] = 1;
map['V' - 'A'] = 5;
map['X' - 'A'] = 10;
map['L' - 'A'] = 50;
map['C' - 'A'] = 100;
map['D' - 'A'] = 500;
map['M' - 'A'] = 1000;
int res = 0, tmp = 0;
for (int i = 0; i < s.size(); i++)
{
if (map[s[i] - 'A'] > tmp)
{
res = res + map[s[i] - 'A'] - tmp * 2;

}
else
{
res = res + map[s[i] - 'A'];
}
tmp = map[s[i] - 'A'];
}
return res;
}
};