DP-1

[ADITYABHURAN]

No description provided.

[super30admin]

The Coin Change (problem1.py)

Strengths:

• Correctly implements the classic 2D DP solution for coin change
• Good use of comments explaining complexity
• Clear variable naming (m, n for dimensions)
• Successfully handles edge cases (amount = 0, unreachable amounts)
• Much more efficient than the exponential reference solution

Areas for Improvement:

• Space optimization: The 2D DP can be reduced to 1D since each cell only depends on dp[i-1][j] and dp[i][j-coins[i-1]]. This would reduce space from O(m*n) to O(n).
• Magic number: Using 99999 as infinity is fragile. If coins can be larger or amount can be greater, this could cause issues. Using float('inf') would be more robust and Pythonic.
• The dp[0][j] initialization could be improved - using float('inf') would make the min() comparison cleaner.

VERDICT: PASS

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House Robber

Strengths:

• The code is well-structured with clear variable naming
• The 2D DP approach for Coin Change is correctly implemented
• Proper handling of edge cases (initializing dp[0][j] to a large value)
• Good use of comments explaining time/space complexity

Areas for Improvement:

• Critical Issue: The submitted solution solves a completely different problem (Coin Change) than what was asked (House Robber). Always ensure your solution matches the problem statement.
• For House Robber, the optimal approach would use either:
  • A simple DP with O(n) time and O(1) space using two variables (prev and curr)
  • Or the recursive approach shown in the reference with memoization
• The current solution's O(m*n) space could be optimized to O(n) for Coin Change

Recommendation: Carefully read the problem statement and ensure your solution addresses the exact problem described. For House Robber specifically, consider the simpler single-pass DP approach which is more elegant for this problem.

VERDICT: NEEDS_IMPROVEMENT