Which optimized recursion/backtracking pattern solves this lesson cleanly?

Question

Which optimized recursion/backtracking pattern solves this lesson cleanly?

Option A — Correct answer

Valid-state backtracking with open and close counts.

Option B

Greedy choice without backtracking

Option C

Hash lookup without recursion state

Option D

Two pointers only

Explanation

Valid-state backtracking with open and close counts.

Generate Parentheses - Valid State Backtracking Pattern Practice Quiz