Roman to Integer LeetCode

Understanding how to convert Roman numerals to integers is essential for anyone preparing for programming challenges on LeetCode or studying historical mathematics. This guide offers a simple and direct method to decode Roman numerals and apply these techniques effectively. Whether you're facing a LeetCode problem or just curious about ancient numeric systems, you'll find the tools you need here to convert Roman numerals accurately to integers.

Problem Statement

Convert a given Roman numeral into its corresponding integer value. Roman numerals are composed of symbols like I (1), V (5), X (10), L (50), C (100), D (500), and M (1000), each representing a specific value.

Examples

• Input: III
  Output: 3
  Explanation: III is composed of three Is, which sum up to 3.

• Input: MCMXCIV
  Output: 1994
  Explanation: MCMXCIV is interpreted as M (1000) + CM (900) + XC (90) + IV (4).

Methods for Converting Roman Numerals to Integers

1. Sequential Addition Method

• Method: Traverse the Roman numeral from left to right, adding values as you go, but subtracting where smaller values precede larger ones. turn integer_value

• Time Complexity: O(n), where 𝑛 is the number of characters in the Roman numeral string.

• Space Complexity: Constant, only a small fixed amount of space is used.

2. Optimized Parsing Approach

• Method: This method improves upon the basic sequential method by using efficient parsing techniques to handle subtractions in a more streamlined manner. integer_value

• Time Complexity: O(n)\, where 𝑛 is the length of the Roman numeral string
• Space Complexity: Constant, using only the space needed to store the Roman numeral and its mapping.

Application

This conversion is not only a great exercise in understanding historical numeral systems but also enhances problem-solving skills in parsing and interpreting data. It's particularly useful for students, educators, historians, and anyone involved in projects where ancient documents need to be understood or analyzed.

Conclusion

Mastering the conversion of Roman numerals to integers opens up a deeper appreciation for ancient civilizations' contributions to mathematical concepts and provides a practical skill for various academic and professional endeavors.