C and C++ are similar. They're technically not subset/superset, but like, 90% of the features in C are also in C++. Idiomatic C++ programming looks very different than idiomatic C programming, but most people who write C++ can write half-decent (albeit maybe not idiomatic) C; and they can learn to write idiomatic C without much of a learning curve, because the fundamentals are the same(low-level data with explicit stack/heap and memory managemnt, no guardrails, old language WATs and footguns).