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I knew the surface stuff: vector is contiguous memory, list is pointer-chained nodes.
Start by defining the core data structures: std::vector as a dynamic array with contiguous memory and std::list as a doubly-linked list with non-contiguous nodes. Then compare their performance characteristics (access, insertion, deletion, memory overhead) and discuss trade-offs in real-world scenarios, especially in low-latency systems like those at ICE. Conclude with guidance on when to choose each based on access patterns, frequency of insertions/deletions, and memory constraints.
Pro tip: Mention that in latency-sensitive trading systems, std::vector is often preferred due to cache locality and predictable performance, but std::list can be useful when stable references and frequent mid-sequence insertions/removals are needed. Also note that std::deque or intrusive lists are sometimes better alternatives, showing deeper knowledge.
Briefly explain that std::vector is a dynamic array with contiguous memory, while std::list is a doubly-linked list with nodes scattered in memory.
Discuss time complexity for access (O(1) vs O(n)), insertion/deletion at ends and middle (amortized O(1) vs O(1) with iterator), and memory overhead (contiguous vs per-node overhead).
Explain that std::list provides stable iterators and references except for erased elements, while std::vector may invalidate them on reallocation or insertion/deletion.
Emphasize that std::vector's contiguous memory leads to better cache locality and performance in practice, especially for traversal, while std::list suffers from cache misses.
Conclude with when to choose each: use std::vector for frequent random access, traversal, and when memory overhead matters; use std::list for frequent insertions/deletions in the middle and when iterator stability is required.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.
Went with templates and overloading for compile-time, virtual functions for runtime.
Start by defining polymorphism as the ability of objects of different types to respond to the same interface, then clearly distinguish compile-time (static) and runtime (dynamic) forms. For each form, explain the mechanism (e.g., function overloading/templates vs. virtual functions) and provide a simple code example. Finally, discuss trade-offs such as performance, flexibility, and design implications, tying back to real-world system design.
Pro tip: Mention that runtime polymorphism via virtual functions introduces a vtable lookup overhead, which can be mitigated by devirtualization or using CRTP for compile-time polymorphism. This shows awareness of performance-critical systems, which is highly relevant for trading platforms.
Give a clear, concise definition: polymorphism allows different types to be treated through a common interface, enabling code reuse and flexibility.
Describe static polymorphism achieved via function overloading, operator overloading, and templates. Emphasize that resolution happens at compile time, leading to zero runtime overhead.
Describe dynamic polymorphism using inheritance and virtual functions. Explain how the vtable and vptr enable dynamic dispatch at runtime, allowing behavior to be determined by the actual object type.
Highlight key differences: compile-time is faster and type-safe but less flexible; runtime is more flexible but incurs overhead and requires careful design (e.g., virtual destructors).
Discuss when to use each form in system design, considering performance, extensibility, and maintainability. For example, use templates for high-performance generic code and virtual functions for plugin architectures.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.