Lessons learned

• Managing a Visual Studio Solution with multiple Projects
• Day 1
  • remembering cctype takes longer than rewriting anything within
  • regex negative lookbehind is still not supported in most languages (shoutouts to powershell 7)
  • awk is still relevant in 2023
• Day 2
  • stringstreams are convenient
• Day 3
  • autoformatting is still broken

  for(std::array<int,2>d:std::array<std::array<int,2>,8>{
     {
        {
           -1,-1
        },{-1,0},{-1,1},{0,-1},{0,1},{1,-1},{1,0},{1,1}
     }}){
     void;
  }

  • using enum exists
• Day 5
  • start-end slices are much easier to reason with than start-range
• Day 7
  • algorithms are convenient and make adding parallel execution easy
• Day 8
  • inputs are too nice
• Day 9
  • from_chars is much faster than istreams, but needs setup
  • consteval from_chars is not real, it cannot hurt you https://godbolt.org/z/73Yqs5cz9
• Day 12
  • span<const T> vs basic_string_view<T>
  • memoization in C++ is hard
• Day 13
  • writing code fast is easier than writing fast code
  • passing functions as template parameters
• Day 16
  • msvc does not do tail call optimization like gcc
• Day 17
  • i should learn A* and stop doing dijkstra every time
• Day 18
  • handparsing integers is faster than from_chars
  • msvc does not like emitting branchless conditional move