During December 2024, work in the geultto/daily-solvetto repository focused on delivering two core features using Java and advanced algorithmic techniques. The first feature implemented itinerary routing by applying depth-first search and graph traversal to compute the lexicographically smallest flight path starting from ICN, ensuring deterministic results through route sorting and robust edge-case handling. The second feature addressed multi-problem solutions, including a genre-based ranking system for songs and a pattern-matching approach to identify unique banned user combinations. Throughout the month, the developer emphasized code quality, clear commit practices, and maintainable data structures, laying a strong foundation for future enhancements.