Sliding Window #01
Medium Longest Substring Without Repeating Characters
Track the longest contiguous substring whose characters stay unique.
Solved sliding windowstringlast seen index
Sliding Window
Grow and shrink a window while maintaining an invariant instead of restarting every substring check. The focus here is window invariants and frequency tracking. Official LeetCode problems are linked on every page instead of being mirrored here.
1 published solutions
3 distinct tags
0 easy / 1 medium / 0 hard difficulty mix
May 21, 2026 most recently updated page
Problems
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