Add Coin Change II and Paint House solutions

[ravithakur2k]

Added CoinChange2.py implementing a memoized recursive solution for the Coin Change II problem. Added PaintHouse.py with three approaches (recursive, DP, and optimized variables) for solving the Paint House problem.

[super30admin]

• Strengths:

  • The student provides multiple solutions, showing a deep understanding of the problem and its optimizations.
  • The code is well-commented and follows best practices, making it easy to understand.
  • The student correctly identifies and explains the time and space complexities of each approach.

• Areas for Improvement:

  • The recursive solution could benefit from memoization to match the reference solution's approach and improve its efficiency.
  • The CoinChange2 solution, while correct, is not relevant to the DP-2 problem being evaluated. It would be better to focus solely on the PaintHouse problem in this context.