Implement a Dependency Resolver in Python

The solution correctly performs topological sorting and raises appropriate errors for circular and missing dependencies. However, its parsing of dependency strings like 'A: , B' would incorrectly include an empty string as a dependency, which is a minor correctness flaw in graph construction.

The solution implements all core features but lacks handling for duplicate package definitions (it overwrites them) and is less robust in parsing malformed dependency strings, which reduces its completeness for real-world inputs.

The code is readable and uses a standard DFS algorithm. The parsing logic is integrated directly into the main function. It is reasonably efficient and not overly complex.

The solution is functional but less robust to common real-world input variations, such as duplicate package definitions or slightly malformed dependency lists, which limits its practical applicability without further refinement.

The solution adheres to the function signature, return type, error types, and specified error message formats. It correctly implements the core requirements.

Correct DFS topological ordering for the target subgraph; cycle detection and missing-package detection generally work. However, trailing commas can produce an empty dependency name that triggers a misleading missing-package error, reducing correctness on loosely formatted inputs.

Meets core requirements (parse, topo sort, cycle/missing errors). Lacks handling of duplicate definitions and doesn’t sanitize empty dep tokens, which are common minor format issues.

Readable and short; uses standard DFS states. Minor issues: path.index lookup inside cycle case and silent overwriting on duplicates; less defensive parsing.

Useful as-is for clean inputs, but less resilient to slightly messy definitions and duplicates, which reduces real-world usefulness.

Implements the requested function and raises ValueError with descriptive messages including a cycle path; returns the correct format.

Answer A correctly implements topological sort via DFS, properly detects circular dependencies with accurate cycle path reporting, detects missing packages, and produces valid installation orders. The core algorithm is correct for all specified test cases.

Answer A handles the main requirements: parsing, topological sort, cycle detection, and missing package detection. However, it does not handle edge cases like duplicate package definitions, empty package names, non-string inputs, or empty strings resulting from splitting dependencies.

Answer A is concise and readable with clear variable names and comments. The code structure is straightforward. However, it lacks a docstring and the parsing logic is inline rather than separated into a helper function.

Answer A is functional and would work in practice for well-formed inputs. However, the lack of input validation for edge cases reduces its robustness in real-world scenarios where inputs may be malformed.

Answer A follows the instructions well: it implements the required function signature, parses the input format, performs topological sort, detects cycles with descriptive messages, and detects missing packages. The error message format matches the examples.

The solution correctly performs topological sorting and raises appropriate errors. It handles various parsing edge cases correctly, such as 'A: , B' not creating an empty string dependency. The cycle detection logic is sound, despite a minor, non-impacting logical oddity in the `try-except` block.

The solution is very complete, implementing all required features including robust parsing, graph building, topological sort, and comprehensive error handling. It correctly addresses duplicate package definitions and various malformed input scenarios.

The code quality is strong, with good modularity achieved by separating parsing into a helper function. It includes a helpful docstring and uses a standard DFS. The `try-except` block in cycle detection is a minor logical oddity but doesn't significantly detract from overall quality.

The solution offers high practical value due to its robust parsing and comprehensive error handling, including detection of duplicate package definitions. This makes it more resilient and reliable for use in a package management system.

The solution meticulously follows all explicit instructions, including function signature, return type, error types, and exact error message formats. It also goes beyond the explicit requirements by providing more robust input parsing, aligning well with the spirit of the task's robustness criterion.

Produces valid topological order ending with the target, no duplicates, correct handling of transitive deps, self-deps, and diamonds. Cycle and missing-package detection are correct and consistent during traversal.

Covers all specified requirements and adds sensible extras (duplicate definition detection, stronger malformed-input checks) without breaking the interface.

Well-structured with helper parsing function, docstring, clear variable naming, and defensive checks. Cycle construction is clear; overall maintainable.

More production-friendly due to validation, duplicate detection, and sanitizing dependency tokens; example usage helps quick verification.

Implements the requested function and error messages; includes extra example main block (not requested) but does not interfere with function behavior.

Answer B correctly implements topological sort via DFS, properly detects circular dependencies with accurate cycle path reporting, detects missing packages, and produces valid installation orders. The core algorithm is correct for all specified test cases. The missing package check is done both upfront and during DFS traversal, which is slightly redundant but not incorrect.

Answer B handles all main requirements plus additional edge cases: duplicate package definitions, empty package names, non-string input validation, and filtering empty dependency strings. It also includes a docstring documenting the interface, arguments, return value, and exceptions.

Answer B has better code organization with a separate parse_definitions helper function, a comprehensive docstring, clear variable names, and inline comments. The separation of concerns makes the code more maintainable and testable.

Answer B is more practical due to its additional input validation, better error messages, and example usage in the __main__ block. The duplicate detection and input type checking make it more suitable for integration into a real package management system.

Answer B follows all instructions and goes slightly beyond by providing a docstring, example usage, and additional validation. The function signature matches exactly, error messages are descriptive and match the required format, and the topological sort is correctly implemented.