Browse 6 Sliding Window Coding Challenge
Turn slow nested loops into fast linear-time coding solutions. Master sliding window problems to handle substring and subarray logic like a pro.
Problems (6 total)
About Sliding Window Problems
Sliding window is one of the cleanest ways to turn slow coding problems into fast linear-time solutions. Instead of a messy scan, you keep a moving range that solves your coding challenge as you go.
This pattern shows up constantly in substring and subarray problems. Sometimes the window size is fixed, sometimes it expands and shrinks depending on a condition. Either way, the main idea is the same: reuse work from the previous step instead of recalculating everything inside the range from scratch.
What makes sliding window tricky is not the movement itself. It is deciding what the window is tracking and what condition keeps it valid. You might be counting characters, sums, distinct values, or frequencies. Once that part is clear, the left and right pointer dance becomes much easier to control.
Budibadu gives you sliding window problems that help you build that rhythm: expand, check, shrink, and keep moving. If you want to get faster at substring and subarray questions without falling back to nested loops, this category is worth challenging yourself with.