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Went with a doubly linked list and first-fit allocation.
Start by clarifying requirements and constraints, then propose a data structure like a free list or bitmap to track memory blocks. Discuss allocation strategies (first-fit, best-fit, worst-fit) and how to handle fragmentation, and finally analyze time/space trade-offs and potential optimizations.
Pro tip: Demonstrate awareness of real-world memory allocators (e.g., buddy system, slab allocation) and mention how your design would scale or handle edge cases like coalescing adjacent free blocks.
Ask about constraints: Is the memory fixed-size? What are typical allocation sizes? Are there real-time constraints? This shows you think before coding.
Propose a free list (linked list of free blocks) or a bitmap to track allocated/free units. Discuss pros and cons of each.
Describe algorithms for allocating X units (e.g., first-fit, best-fit) and freeing a region, including coalescing adjacent free blocks to reduce fragmentation.
Compare time complexity (O(n) for first-fit vs. O(log n) with balanced trees) and space overhead. Discuss fragmentation and mitigation strategies.
Suggest improvements like segregated free lists, buddy system, or using a balanced tree for faster allocation. Mention how to handle edge cases (e.g., allocation failure).
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.