Roman to Integer Converter

Given a roman numeral, convert it to an integer. Roman numerals are represented by seven different symbols: `I` (1), `V` (5), `X` (10), `L` (50), `C` (100), `D` (500) and `M` (1000). When a smaller numeral appears before a larger one (e.g. IV = 4, IX = 9, XL = 40, XC = 90, CD = 400, CM = 900), subtraction is used instead of addition. ### Constraints - `1 <= s.length <= 15` - `s` contains only the characters ('I', 'V', 'X', 'L', 'C', 'D', 'M'). - Guaranteed to be a valid roman numeral in the range [1, 3999]. ### Input Format A single line containing the roman numeral string `s`. ### Output Format Print the equivalent integer value.