↩ 🔵 🔵 🔵 ❪✺₄❫ C++ Sets ○ ❪✺_❫ C++ Subs ○ ❪✺_ₛₛ❫ C Subsets ○ ❪✺_ₛₛ₀❫ Language Subsets ○ ❪✺_ₜₛ❫ C++ Typesets ○