Grow-Shrink Window · Variable window / distinct count
Longest Substring Without Repeating
LeetCode 3 · Module: Pointers & Windows
The scenario
you are tracking a live segment, the active users, the current substring, the open interval, and the answer changes as the boundaries move.
What you'll learn
- How to recognize the Grow-Shrink Window pattern from the problem statement.
- The BASIC Framework breakdown for this problem.
- A clean, interview-ready Python solution with time/space analysis.
Full video, code, and the workspace are part of PatternMastery Pro, 500 problems in a $19.99/year subscription.