Last Updated: November 15, 2025
Sliding window is a powerful problem-solving pattern where you use two pointers to define a “window” and slide them over a data structure, typically an array or a string to find subarrays or substrings that meet a certain requirement.
Using this approach, you can reduce the time complexity of many array and string related problems from O(n²) to O(n).
In this chapter, I’ll break down: