During December 2025, Kyh developed a stack-based Parentheses Validation Function for the DaleStudy/leetcode-study repository, focusing on robust input validation for problem-solving exercises. Using JavaScript and leveraging algorithm development and data structures expertise, Kyh designed the function to accurately check for correct nesting and pairing of parentheses and brackets within strings. The implementation addressed edge cases such as empty inputs and mismatched delimiters, ensuring deterministic validation outcomes. The code was structured for clarity and future extensibility, with documentation outlining potential support for additional delimiter types. No major bugs were reported, reflecting a focus on code quality and maintainability throughout the month.