Divide & Conquer

Divide and conquer splits a problem into independent subproblems, solves each recursively, and merges the results — the structure behind merge sort, quickselect, and many O(n log n) algorithms. Use it when a problem cleanly halves and the merge is cheaper than brute force.

4 LeetCode problems solved with the Divide & Conquer pattern. Practice them with spaced repetition so the pattern sticks.

• Construct Quad TreeMEDIUM · O(n^2 log n)
• Convert Sorted Array to Binary Search TreeEASY · O(n)
• Pow(x, n)MEDIUM · O(log n)
• Sort ListMEDIUM · O(n log n)