Compile Time Accumulate

C++ template metaprogramming: compile-time accumulation

This is a hard C++ problem that tests deep knowledge of template specialization and compile-time computation. It requires you to implement a generic template structure that performs a sum operation entirely during compilation, with the result available as a compile-time constant.

The core challenge is understanding how to recursively specialize templates to iterate through a parameter pack and accumulate values. You must handle both the general case (non-empty pack) and the base case (empty pack) correctly, and expose the computed result as a static constant that the compiler can evaluate during the build phase. Firms like trading desks and high-performance computing teams ask this kind of question to verify that you understand how C++ templates work at a fundamental level, not just how to use them.

• Template specialization and partial specialization
• Variadic templates and parameter packs
• Recursive template instantiation
• Static assertions and compile-time constants