Siemens Coding Question – Solved

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To solve this problem effectively, start by understanding the data and the sorting criteria clearly. You are given a collection of books, each characterized by three attributes: name, author, and edition. The goal is to sort the books so the shelf looks orderly and makes it easier for people to find what they want.

Step 1: Clarify the identification and sorting rules for books
- Each book is defined by a name (title), an author, and an edition.
- Books that have the same name and author but different editions are considered different editions of the same book.
- Your function should treat these editions distinctly and arrange the books in a meaningful order.

Step 2: Understand the natural sorting order
- A typical way to sort books is to first sort alphabetically by author’s name.
- Within the same author, sort alphabetically by book name.
- Within books with the same author and name, sort numerically by edition.
- This hierarchical sorting ensures that books by the same author stay together, and different editions of the same book are grouped and sorted properly.

Step 3: Consider data structures to hold the book data
- You can represent each book as a structure or an object with three fields: name (string), author (string), and edition (integer).
- Since sorting involves multiple criteria, a composite key can be used, such as (author, name, edition).

Step 4: Plan the sorting mechanism
- Use a sorting function or algorithm that supports custom comparison logic.
- When comparing two books:
- First, compare the authors lexicographically.
- If authors are the same, compare the book names lexicographically.
- If both author and name match, compare the editions numerically.
- The comparison should be stable to maintain relative ordering where appropriate.

Step 5: Handle case sensitivity and whitespace
- Decide on case sensitivity: do you want the sorting to be case-insensitive? Usually, sorting alphabetically ignores case.
- Trim any leading or trailing whitespace from the strings to avoid sorting errors.
- Normalize the data if needed, e.g., convert all strings to lowercase before comparison.

Step 6: Edge cases and validation
- Handle empty fields or missing information gracefully.
- If edition information is missing or invalid, decide on a default behavior (e.g., treat as edition 0 or place at the end).
- Be mindful of books that may have the same name but different authors.

Step 7: Implement the sorting
- Sort the entire list of books using the multi-level criteria.
- If your environment or language supports it, use built-in sorting functions with custom comparators.
- Otherwise, implement a sorting algorithm (like merge sort or quicksort) with the comparison logic.

Step 8: Output format
- After sorting, output the books in the sorted order, displaying their name, author, and edition clearly.
- Ensure the output is consistent and readable, possibly aligning the fields or using a standardized format.

Step 9: Performance considerations
- Since the number of books can be large, use an efficient sorting algorithm with O(N log N) complexity.
- Avoid unnecessary string operations inside the comparison function to optimize speed.
- If sorting stability matters, pick or implement a stable sorting method.

Step 10: Testing
- Test your function with various inputs:
- Books with same author and different names.
- Books with same author and name but different editions.
- Books with different authors.
- Books with mixed case and whitespace.
- Verify the output matches the expected sorted order.

In summary, the core idea is to use a multi-level sorting approach prioritizing author, then name, then edition. Clean and normalize data for consistent comparison, handle edge cases thoughtfully, and use efficient sorting mechanisms. By doing so, your function will produce an organized and user-friendly arrangement of books on the shelves.
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