Core Idea: Function calls itself to break big problems into smaller identical ones. Add backtracking to explore all possibilities and undo choices.
When to use: Subsets, permutations, combinations, or maze/path problems.
🗯Real Interview Scenario:
Generate all subsets
or “Word Search” in a grid.
✅ How to shine: Explain:
I’ll use recursion with backtracking to try choices and undo them.
Draw the recursion tree verbally. Always define clear base case first. Watch stack depth for large inputs.
Practice 4-5 problems. Once comfortable, you’ll handle many medium/hard questions confidently.