Done with DP-1

[RitikaC1]

No description provided.

[super30admin]

The Coin Change (problem-1.py)

Strengths:

1. Clean, well-commented code with clear documentation of time/space complexity
2. Efficient 1D DP solution that avoids unnecessary space usage
3. Good variable naming (matrix for DP table)
4. Proper handling of edge cases (amount=0 returns 0, unreachable amounts return -1)
5. The commented first approach shows understanding of 2D DP as well

Areas for Improvement:

1. The variable name matrix is misleading for a 1D array - consider dp or minCoins
2. The solution could benefit from early termination if amount is 0 (though it handles it correctly)
3. Consider adding a check for empty coins list (though constraints guarantee at least 1 coin)
4. The commented-out 2D approach has a minor issue: matrix[0][i]=float('inf') should be float('inf') for all amounts except 0, but the current implementation is fine for the working approach

Time Complexity: O(N*M) where N is number of coins and M is amount - this is optimal for this problem
Space Complexity: O(M) - optimal compared to reference solution's O(m+n) stack space

VERDICT: PASS

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House Robber (problem-2.py)

Strengths:

1. Excellent time complexity of O(N) - significantly better than the reference solution's O(2^N) exponential time
2. Optimal space complexity of O(1) - only two variables are used regardless of input size
3. Clean, readable code with appropriate variable names
4. Handles edge cases (n == 1) appropriately
5. Good use of temporary variable to swap values correctly

Areas for Improvement:

1. The solution could benefit from more detailed comments explaining the DP logic
2. Consider adding handling for empty arrays (though constraints say length >= 1)
3. The variable name "robbings" in the reference solution is misspelled - your naming is better

Comparison to Reference:

• Your solution is far more efficient: O(N) vs O(2^N) time complexity
• Your solution uses O(1) space vs O(N) space from the reference's recursion stack
• The reference solution uses naive recursion while your solution uses optimized DP

VERDICT: PASS