My C++ Learnings

AKA These are the reasons to some weird errors/behaviours I encountered

• Why templates declared in header file and defined in a translation unit need to be instantiated explicitly

  • https://stackoverflow.com/questions/495021/why-can-templates-only-be-implemented-in-the-header-file
  • https://stackoverflow.com/questions/13269116/template-classes-multiple-file-project-how-to
  • https://stackoverflow.com/questions/3749099/why-should-the-implementation-and-the-declaration-of-a-template-class-be-in-the

• Allocated memory is not zeroed

  • https://stackoverflow.com/questions/47834180/set-an-array-to-zero-with-c11
  • https://stackoverflow.com/questions/9146395/reset-c-int-array-to-zero-the-fastest-way
  • Personally use for (T &elem : arr) elem = 0; for resetting and T arr = {0}; for initialisation

• Lookup tables are fast, for small tables an integer can be used to hold the table

  • https://stackoverflow.com/a/47846874/10540048
  • For larger N (N>64/128/25), allocating memory for the table is the best way