You've learned the divide and conquer approach: divide, conquer, combine.
Classic algorithms:
- Merge sort: sorting.
- Binary search: lookup.
- QuickSelect: expected selection.
- Karatsuba: multiplication.
Master Theorem: solves most D&C recurrences.
When to use D&C:
- Problem splits into independent subproblems.
- Subproblem structure matches original problem.
- Combination step is efficient.
D&C is a thinking framework. When you see a problem, ask: "Can I split this, solve pieces, and merge?" Many efficient algorithms follow this pattern.