The Coin Change (coin_change.cpp)

Strengths:

• Correctly implements a bottom-up dynamic programming solution
• Good handling of edge cases (empty coins, amount of 0)
• Uses appropriate sentinel value (amount+1) for impossible cases
• Clear variable naming and logical structure

Areas for Improvement:

• Space complexity could be optimized to O(n) using a 1D DP array instead of 2D, since each row only depends on the current row and previous row
• The commented-out recursive solution has a bug: it doesn't handle the case where both recursive calls return -1
• Could add comments explaining the DP logic for better readability
• The initialization loop for dp[0][i] should use amount+1, but the condition check uses amount+1 which is correct

Minor Issues:

• The code structure is slightly confusing with commented-out code mixed in
• Could benefit from early return optimization for amount == 0

VERDICT: PASS

House Robber (house_robber.cpp)

Strengths:

1. Excellent problem-solving approach by showing multiple solutions with increasing optimization
2. Clear and detailed comments explaining the logic behind each approach
3. Correct implementation of all three methods
4. Good variable naming convention (skip/take) makes the code self-documenting
5. Proper handling of edge cases (n=1 handled correctly in Approach 3)

Areas for Improvement:

1. The recursive approach could benefit from memoization to reduce time from O(2^n) to O(n)
2. Consider adding a main function or test cases to demonstrate the solution's correctness
3. The commented-out code could be removed for cleaner submission, or kept if intentionally showing progression

Minor Suggestions:

• In Approach 3, the variable temp could be named more descriptively (e.g., prevSkip)
• Adding a brief explanation of why the space-optimized approach works would improve documentation

VERDICT: PASS