Sliding Window LeetCode Problems: All 116, With Python Solutions
Every problem in this library that LeetCode tags Sliding Window — 116 in total, 102 of them with a complete Python solution, a worked example and the time and space complexity of the approach.
- 116 problems
- 12 Easy
- 74 Medium
- 30 Hard
How Sliding Window problems are solved
A tag names the subject, not the method. These pattern hubs cover the techniques that actually solve Sliding Window problems — each one explains the approach, gives a Python template and states its complexity.
- Sliding Window — Collapse a nested loop over every subarray into a single pass with two indices.
Sliding Window problems by difficulty
Problems with a complete Python solution are listed first, then by ascending problem number.
Easy (12)
| # | Problem | Difficulty | Topics |
|---|---|---|---|
| 219 | Contains Duplicate II | Easy | Array, Hash Table, Sliding Window |
| 594 | Longest Harmonious Subsequence | Easy | Array, Hash Table, Counting +2 |
| 643 | Maximum Average Subarray I | Easy | Array, Sliding Window |
| 1652 | Defuse the Bomb | Easy | Array, Sliding Window |
| 1763 | Longest Nice Substring | Easy | Bit Manipulation, Hash Table, String +2 |
| 1876 | Substrings of Size Three with Distinct Characters | Easy | Hash Table, String, Counting +1 |
| 1984 | Minimum Difference Between Highest and Lowest of K Scores | Easy | Array, Sorting, Sliding Window |
| 2269 | Find the K-Beauty of a Number | Easy | Math, String, Sliding Window |
| 2379 | Minimum Recolors to Get K Consecutive Black Blocks | Easy | String, Sliding Window |
| 2760 | Longest Even Odd Subarray With Threshold | Easy | Array, Sliding Window |
| 2932 | Maximum Strong Pair XOR I | Easy | Bit Manipulation, Trie, Array +2 |
| 1176 | Diet Plan PerformancePremium | Easy | Array, Sliding Window |
Medium (74)
| # | Problem | Difficulty | Topics |
|---|---|---|---|
| 3 | Longest Substring Without Repeating Characters | Medium | Hash Table, String, Sliding Window |
| 187 | Repeated DNA Sequences | Medium | Bit Manipulation, Hash Table, String +3 |
| 209 | Minimum Size Subarray Sum | Medium | Array, Binary Search, Prefix Sum +1 |
| 395 | Longest Substring with At Least K Repeating Characters | Medium | Hash Table, String, Divide and Conquer +1 |
| 413 | Arithmetic Slices | Medium | Array, Dynamic Programming, Sliding Window |
| 424 | Longest Repeating Character Replacement | Medium | Hash Table, String, Sliding Window |
| 438 | Find All Anagrams in a String | Medium | Hash Table, String, Sliding Window |
| 567 | Permutation in String | Medium | Hash Table, Two Pointers, String +1 |
| 658 | Find K Closest Elements | Medium | Array, Two Pointers, Binary Search +3 |
| 713 | Subarray Product Less Than K | Medium | Array, Binary Search, Prefix Sum +1 |
| 718 | Maximum Length of Repeated Subarray | Medium | Array, Binary Search, Dynamic Programming +3 |
| 837 | New 21 Game | Medium | Math, Dynamic Programming, Sliding Window +1 |
| 904 | Fruit Into Baskets | Medium | Array, Hash Table, Sliding Window |
| 930 | Binary Subarrays With Sum | Medium | Array, Hash Table, Prefix Sum +1 |
| 978 | Longest Turbulent Subarray | Medium | Array, Dynamic Programming, Sliding Window |
| 1004 | Max Consecutive Ones III | Medium | Array, Binary Search, Prefix Sum +1 |
| 1016 | Binary String With Substrings Representing 1 To N | Medium | Bit Manipulation, Hash Table, String +1 |
| 1031 | Maximum Sum of Two Non-Overlapping Subarrays | Medium | Array, Dynamic Programming, Sliding Window |
| 1040 | Moving Stones Until Consecutive II | Medium | Array, Math, Sorting +1 |
| 1052 | Grumpy Bookstore Owner | Medium | Array, Sliding Window |
| 1156 | Swap For Longest Repeated Character Substring | Medium | Hash Table, String, Sliding Window |
| 1208 | Get Equal Substrings Within Budget | Medium | String, Binary Search, Prefix Sum +1 |
| 1234 | Replace the Substring for Balanced String | Medium | String, Sliding Window |
| 1248 | Count Number of Nice Subarrays | Medium | Array, Hash Table, Math +2 |
| 1297 | Maximum Number of Occurrences of a Substring | Medium | Hash Table, String, Sliding Window |
| 1343 | Number of Sub-arrays of Size K and Average Greater than or Equal to Threshold | Medium | Array, Sliding Window |
| 1358 | Number of Substrings Containing All Three Characters | Medium | Hash Table, String, Sliding Window |
| 1423 | Maximum Points You Can Obtain from Cards | Medium | Array, Prefix Sum, Sliding Window |
| 1438 | Longest Continuous Subarray With Absolute Diff Less Than or Equal to Limit | Medium | Queue, Array, Ordered Set +3 |
| 1456 | Maximum Number of Vowels in a Substring of Given Length | Medium | String, Sliding Window |
| 1477 | Find Two Non-overlapping Sub-arrays Each With Target Sum | Medium | Array, Hash Table, Binary Search +2 |
| 1493 | Longest Subarray of 1's After Deleting One Element | Medium | Array, Dynamic Programming, Sliding Window |
| 1658 | Minimum Operations to Reduce X to Zero | Medium | Array, Hash Table, Binary Search +2 |
| 1695 | Maximum Erasure Value | Medium | Array, Hash Table, Sliding Window |
| 1838 | Frequency of the Most Frequent Element | Medium | Greedy, Array, Binary Search +3 |
| 1839 | Longest Substring Of All Vowels in Order | Medium | String, Sliding Window |
| 1871 | Jump Game VII | Medium | String, Dynamic Programming, Prefix Sum +1 |
| 1888 | Minimum Number of Flips to Make the Binary String Alternating | Medium | String, Dynamic Programming, Sliding Window |
| 2024 | Maximize the Confusion of an Exam | Medium | String, Binary Search, Prefix Sum +1 |
| 2090 | K Radius Subarray Averages | Medium | Array, Sliding Window |
| 2110 | Number of Smooth Descent Periods of a Stock | Medium | Array, Math, Two Pointers +2 |
| 2134 | Minimum Swaps to Group All 1's Together II | Medium | Array, Sliding Window |
| 2260 | Minimum Consecutive Cards to Pick Up | Medium | Array, Hash Table, Sliding Window |
| 2271 | Maximum White Tiles Covered by a Carpet | Medium | Greedy, Array, Binary Search +3 |
| 2401 | Longest Nice Subarray | Medium | Bit Manipulation, Array, Sliding Window |
| 2411 | Smallest Subarrays With Maximum Bitwise OR | Medium | Bit Manipulation, Array, Binary Search +1 |
| 2461 | Maximum Sum of Distinct Subarrays With Length K | Medium | Array, Hash Table, Sliding Window |
| 2516 | Take K of Each Character From Left and Right | Medium | Hash Table, String, Sliding Window |
| 2537 | Count the Number of Good Subarrays | Medium | Array, Hash Table, Sliding Window |
| 2555 | Maximize Win From Two Segments | Medium | Array, Binary Search, Sliding Window |
| 2653 | Sliding Subarray Beauty | Medium | Array, Hash Table, Sliding Window |
| 2730 | Find the Longest Semi-Repetitive Substring | Medium | String, Sliding Window |
| 2747 | Count Zero Request Servers | Medium | Array, Hash Table, Sorting +1 |
| 2762 | Continuous Subarrays | Medium | Queue, Array, Ordered Set +3 |
| 2779 | Maximum Beauty of an Array After Applying Operation | Medium | Array, Binary Search, Sorting +1 |
| 2799 | Count Complete Subarrays in an Array | Medium | Array, Hash Table, Sliding Window |
| 2831 | Find the Longest Equal Subarray | Medium | Array, Hash Table, Binary Search +1 |
| 2841 | Maximum Sum of Almost Unique Subarray | Medium | Array, Hash Table, Sliding Window |
| 2875 | Minimum Size Subarray in Infinite Array | Medium | Array, Hash Table, Prefix Sum +1 |
| 2904 | Shortest and Lexicographically Smallest Beautiful String | Medium | String, Sliding Window |
| 2958 | Length of Longest Subarray With at Most K Frequency | Medium | Array, Hash Table, Sliding Window |
| 2962 | Count Subarrays Where Max Element Appears at Least K Times | Medium | Array, Sliding Window |
| 2981 | Find Longest Special Substring That Occurs Thrice I | Medium | Hash Table, String, Binary Search +2 |
| 2982 | Find Longest Special Substring That Occurs Thrice II | Medium | Hash Table, String, Binary Search +2 |
| 159 | Longest Substring with At Most Two Distinct CharactersPremium | Medium | Hash Table, String, Sliding Window |
| 340 | Longest Substring with At Most K Distinct CharactersPremium | Medium | Hash Table, String, Sliding Window |
| 487 | Max Consecutive Ones IIPremium | Medium | Array, Dynamic Programming, Sliding Window |
| 1100 | Find K-Length Substrings With No Repeated CharactersPremium | Medium | Hash Table, String, Sliding Window |
| 1151 | Minimum Swaps to Group All 1's TogetherPremium | Medium | Array, Sliding Window |
| 1852 | Distinct Numbers in Each SubarrayPremium | Medium | Array, Hash Table, Sliding Window |
| 1918 | Kth Smallest Subarray SumPremium | Medium | Array, Binary Search, Sliding Window |
| 2067 | Number of Equal Count SubstringsPremium | Medium | Hash Table, String, Counting +1 |
| 2107 | Number of Unique Flavors After Sharing K CandiesPremium | Medium | Array, Hash Table, Sliding Window |
| 2743 | Count Substrings Without Repeating CharacterPremium | Medium | Hash Table, String, Sliding Window |
Hard (30)
| # | Problem | Difficulty | Topics |
|---|---|---|---|
| 30 | Substring with Concatenation of All Words | Hard | Hash Table, String, Sliding Window |
| 76 | Minimum Window Substring | Hard | Hash Table, String, Sliding Window |
| 220 | Contains Duplicate III | Hard | Array, Bucket Sort, Ordered Set +2 |
| 239 | Sliding Window Maximum | Hard | Queue, Array, Sliding Window +2 |
| 480 | Sliding Window Median | Hard | Array, Hash Table, Sliding Window +1 |
| 632 | Smallest Range Covering Elements from K Lists | Hard | Greedy, Array, Hash Table +3 |
| 689 | Maximum Sum of 3 Non-Overlapping Subarrays | Hard | Array, Dynamic Programming, Prefix Sum +1 |
| 862 | Shortest Subarray with Sum at Least K | Hard | Queue, Array, Binary Search +4 |
| 992 | Subarrays with K Different Integers | Hard | Array, Hash Table, Counting +1 |
| 995 | Minimum Number of K Consecutive Bit Flips | Hard | Bit Manipulation, Queue, Array +2 |
| 1044 | Longest Duplicate Substring | Hard | String, Binary Search, Suffix Array +3 |
| 1425 | Constrained Subsequence Sum | Hard | Queue, Array, Dynamic Programming +3 |
| 1499 | Max Value of Equation | Hard | Queue, Array, Sliding Window +2 |
| 1610 | Maximum Number of Visible Points | Hard | Geometry, Array, Math +2 |
| 1703 | Minimum Adjacent Swaps for K Consecutive Ones | Hard | Greedy, Array, Prefix Sum +1 |
| 2009 | Minimum Number of Operations to Make Array Continuous | Hard | Array, Hash Table, Binary Search +1 |
| 2106 | Maximum Fruits Harvested After at Most K Steps | Hard | Array, Binary Search, Prefix Sum +1 |
| 2156 | Find Substring With Given Hash Value | Hard | String, Sliding Window, Hash Function +1 |
| 2302 | Count Subarrays With Score Less Than K | Hard | Array, Binary Search, Prefix Sum +1 |
| 2398 | Maximum Number of Robots Within Budget | Hard | Queue, Array, Binary Search +4 |
| 2444 | Count Subarrays With Fixed Bounds | Hard | Queue, Array, Sliding Window +1 |
| 2528 | Maximize the Minimum Powered City | Hard | Greedy, Queue, Array +3 |
| 2781 | Length of the Longest Valid Substring | Hard | Array, Hash Table, String +1 |
| 2902 | Count of Sub-Multisets With Bounded Sum | Hard | Array, Hash Table, Dynamic Programming +1 |
| 2935 | Maximum Strong Pair XOR II | Hard | Bit Manipulation, Trie, Array +2 |
| 2953 | Count Complete Substrings | Hard | Hash Table, String, Sliding Window |
| 2968 | Apply Operations to Maximize Frequency Score | Hard | Array, Binary Search, Prefix Sum +2 |
| 683 | K Empty SlotsPremium | Hard | Binary Indexed Tree, Segment Tree, Queue +5 |
| 727 | Minimum Window SubsequencePremium | Hard | String, Dynamic Programming, Sliding Window |
| 2524 | Maximum Frequency Score of a SubarrayPremium | Hard | Stack, Array, Hash Table +2 |
Keep exploring
All LeetCode topicsEvery tag with a page of its own, with the number of problems behind each.LeetCode patternsThe techniques themselves, with a Python template and complexity for each.Curated study listsBlind 75, NeetCode 150 and three more, grouped by pattern.Easy problemsStart here when the data structure is new rather than the problem.
Other topics
- Array1,569
- String672
- Hash Table588
- Math485
- Dynamic Programming481
- Sorting392
- Greedy346
- Depth-First Search289
- Binary Search253
- Database249
- Tree225
- Breadth-First Search223
- Matrix216
- Two Pointers201
- Bit Manipulation194
- Binary Tree174
- Heap (Priority Queue)163
- Prefix Sum157
- Stack157
- Simulation144
- Graph138
- Counting126
- Design122
- Backtracking105
When the Sliding Window problem arrives live
Stealth Interview is a desktop app for macOS and Windows. It reads the coding problem off your screen, returns a working solution with a step-by-step explanation and its time and space complexity, and transcribes what the interviewer is saying — while staying invisible to screen sharing.