MediumVery High Frequency25 min

Sliding Window vs Two Pointers vs Prefix Sum

Know exactly when to use each array technique and avoid common confusions.

Master recognizing which pattern to apply: two pointers vs sliding window vs binary search vs DP vs backtracking. Learn the decision tree.

Pattern Decision Tree

More in Pattern Recognition Center

Keyword → Pattern Decision Tree

Map problem keywords to the correct algorithm — subarray, K largest, shortest path, count ways and more.

Interview Shortcuts & Tricks

XOR tricks, fast modular arithmetic, bit manipulation shortcuts, and common optimizations.

Keyword → Pattern Decision Tree

Interview Shortcuts & Tricks