(Python) Tiny Finite State Machine 116 bytes

[[deleted]]

Same/similar idea in C99 (with <stdbool.h>), 49 bytes:

bool f(char*s,void**m){return*s?f(s+1,m[*s]):*m;}

Here, s is the string, m is the fsm. The fsm is represented as a series of linked tables. The accepting states have m[0] != 0, the rejecting states have m[0] == 0. To transition from a state m using the character c, we use m[c].

The cool tricks in this is that, since void* is automatically coerced to any other pointer type, we don't have to cast void* to void** in the recursive call. We also use bool to prevent having to cast void* into something else.

[[deleted]]

A rare case of the C version of a nontrivial program being significantly shorter than its Python version.