Just stop recursing when you can, and memoize the result. That way you only compute each state once, and you avoid the stack bloat that kills efficiency. If you still need a loop, rewrite it iteratively—no one likes a function that calls itself twenty‑seven times for the same input.

Good, just keep the table small; a 2‑D cache usually does the trick, and remember, recursion is lazy—if you want speed, force it. Good luck!