Strengths:

• The student has demonstrated a strong understanding of both problems and provided efficient solutions.
• The code is clean, well-commented, and follows best practices.
• The inclusion of test cases in the main method is excellent for verifying correctness.

Areas for Improvement:

• For the twoSum problem, while the solution is correct, it might be worth mentioning that the space complexity could be a concern for very large input sizes. However, this is a trade-off for the improved time complexity.
• The knapsack problem solution is optimal, but adding a brief comment explaining the reasoning behind iterating backwards in the inner loop could help clarify the approach for readers.