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LeetCode难题代码和算法要点分析

目前分类目录

Two Pointers

011.Container-With-Most-Water (M+)
015.3Sum (M)
016.3Sum-Closet (M)
018.4Sum (M)
259.3Sum-Smaller (M+)
030.Substring-with-Concatenation-of-All-Words (H)
075.Sort-Colors (M+)
076.Minimum Window Substring (M+)
026.Remove Duplicates from Sorted Array (H-)
080.Remove Duplicates from Sorted Array II (H)
209.Minimum-Size-Subarray-Sum (M)
088.Merge Sorted Array (M)
283.Move-Zeroes (M)
141.Linked-List-Cycle (E+)
142.Linked-List-Cycle-II (M+)
287.Find-the-Duplicate-Number (H)
532.K-diff-Pairs-in-an-Array (H-)
360.Sort-Transformed-Array (M)
611.Valid-Triangle-Number (M+)
713.Subarray-Product-Less-Than-K (M+)
1004.Max-Consecutive-Ones-III (M)
1052.Grumpy-Bookstore-Owner (M)
1234.Replace-the-Substring-for-Balanced-String (H-)
1498.Number-of-Subsequences-That-Satisfy-the-Given-Sum-Condition (H-)
1574.Shortest-Subarray-to-be-Removed-to-Make-Array-Sorted (H-)
1577.Number-of-Ways-Where-Square-of-Number-Is-Equal-to-Product-of-Two-Numbers (H-)
1580.Put-Boxes-Into-the-Warehouse-II (H-)
1537.Get-the-Maximum-Score (H-)

• Distinct Characters
  003.Longest-Substring-Without-Repeating-Character (E+)
  159.Longest-Substring-with-At-Most-Two-Distinct-Characters(H-)
  340.Longest-Substring-with-At-Most-K-Distinct-Characters (H)
  992.Subarrays-with-K-Different-Integers (H-)

Binary Search

004.Median-of-Two-Sorted-Arrays (H)
154.Find-Minimum-in-Rotated-Sorted-Array-II (H-)    
033.Search-in-Rotated-Sorted-Array (M)
081.Search-in-Rotated-Sorted-Array-II (M)
034.Search-for-a-Range (M)
162.Find-Peak-Element (H-)
222.Count-Complete-Tree-Nodes (H-)
275.H-index II (H)
302.Smallest-Rectangle-Enclosing-Black-Pixels (M+)
410.Split-Array-Largest-Sum (H)
475.Heaters (H-)
483.Smallest-Good-Base (H)
029.Divide-Two-Integers (M+)
644.Maximum-Average-Subarray-II (H)
658.Find-K-Closest-Elements (H)
1102.Path-With-Maximum-Minimum-Value (H-)
1095.Find-in-Mountain-Array (TBD)
1157.Online-Majority-Element-In-Subarray (H-)
1201.Ugly-Number-III (TBD)
1483.Kth-Ancestor-of-a-Tree-Node (H)
1533.Find-the-Index-of-the-Large-Integer (M)

• Binary Search by Value
  215.Kth-Largest-Element-in-an-Array (M)
  287.Find-the-Duplicate-Number (H-)
  378.Kth-Smallest-Element-in-a-Sorted-Matrix (H-)
  373.Find-K-Pairs-with-Smallest-Sums (H)
  668.Kth-Smallest-Number-in-Multiplication-Table (H-)
  719.Find-K-th-Smallest-Pair-Distance (H-)
  774.Minimize-Max-Distance-to-Gas-Station (H)
  786.K-th-Smallest-Prime-Fraction (H-)
  793.Preimage-Size-of-Factorial-Zeroes-Function (H-)
  1060.Missing-Element-in-Sorted-Array (H)
  1539.Kth-Missing-Positive-Number (H-)
  1201.Ugly-Number-III (H-)
  1231.Divide-Chocolate (M)
  1283.Find-the-Smallest-Divisor-Given-a-Threshold (M)
  1292.Maximum-Side-Length-of-a-Square-with-Sum-Less-than-or-Equal-to-Threshold (H-)
  1300.Sum-of-Mutated-Array-Closest-to-Target (M+)
  1482.Minimum-Number-of-Days-to-Make-m-Bouquets (M)
  1508.Range-Sum-of-Sorted-Subarray-Sums (M+)
  1552.Magnetic-Force-Between-Two-Balls (M)
  1608.Special-Array-With-X-Elements-Greater-Than-or-Equal-X (M+)
  1648.Sell-Diminishing-Valued-Colored-Balls (H-)

Hash Table

049.Group-Anagrams (M+)
149.Max-Points-on-a-Line (H)
166.Fraction-to-Recurring-Decimal (M)
170.Two-Sum-III-Data-structure-design (M)
392.Is-Subsequence (H-)
204.Count Primes (M)
274.H-Index (H)
325.Maximum-Size-Subarray-Sum-Equals-k (M)
409.Longest-Palindrome (M)
447.Number-of-Boomerangs (E+)
438.Find-All-Anagrams-in-a-String (M+)
525.Contiguous-Array (M)
356.Line-Reflection (H-)
594.Longest-Harmonious-Subsequence (M+)
532.K-diff-Pairs-in-an-Array (E+)
424.Longest-Repeating-Character-Replacement （H）
446.Arithmetic-Slices-II-Subsequence (H)
128.Longest-Consecutive-Sequence (H-)
753.Cracking-the-Safe (H)
939.Minimum-Area-Rectangle (M+)
982.Triples-with-Bitwise-AND-Equal-To-Zero (M+) (TBD)
1074.Number-of-Submatrices-That-Sum-to-Target (M+)
1224.Maximum-Equal-Frequency (H-)
1487.Making-File-Names-Unique (M+)
1573.Number-of-Ways-to-Split-a-String (M)

• Hash+Prefix
  930.Binary-Subarrays-With-Sum (M)
  1371.Find-the-Longest-Substring-Containing-Vowels-in-Even-Counts (H-)
  1542.Find-Longest-Awesome-Substring (H)
  1567.Maximum-Length-of-Subarray-With-Positive-Product (M+)
  1590.Make-Sum-Divisible-by-P (H-)

Heap

295.Find-Median-from-Data-Stream (M)
363.Max-Sum-of-Rectangle-No-Larger-Than-K (H)
352.Data-Stream-as-Disjoint-Intervals (H)
480.Sliding-Window-Median (H)
218.The-Skyline-Problem (H)
699.Falling-Squares (H)
715.Range-Module (H)
729.My-Calendar-I (M)
975.Odd-Even-Jump (H-)
1348.Tweet-Counts-Per-Frequency (H-)
1439. Find the Kth Smallest Sum of a Matrix With Sorted Rows (TBD)
1606.Find-Servers-That-Handled-Most-Number-of-Requests (M)

Tree

270.Closest-Binary-Search-Tree-Value (M+)
095.Unique-Binary-Search-Trees-II (H)
094.Binary Tree Inorder Traversal (H-)
144.Binary-Tree-Preorder-Traversal (M+)
145.Binary-Tree-Postorder-Traversal (H-)
110.Balanced-Binary-Tree (M+)
124.Binary-Tree-Maximum-Path-Sum (M+)
222.Count-Complete-Tree-Nodes (M+)
236.Lowest-Common-Ancestor-of-a-Binary-Tree (H)
297.Serialize-and-Deserialize-Binary-Tree （H-）
105.Construct-Binary-Tree-from-Preorder-and-Inorder-Traversal (H-)
106.Construct-Binary-Tree-from-Inorder-and-Postorder-Traversal (M+)
099.Recover-Binary-Search-Tree (H)
114.Flatten-Binary-Tree-to-Linked-List (M+)
098.Validate-Binary-Search-Tree (M)
117.Populating Next Right Pointers in Each Node II (H)
156.Binary-Tree-Upside-Down (H)
285.Inorder-Successor-in-BST (M)
298.Binary-Tree-Longest-Consecutive Sequence (M+)
450.Delete-Node-in-a-BST (H)
437.Path-Sum-III (H-)
449.Serialize-and-Deserialize-BST (H)
333.Largest-BST-Subtree (H)
543.Diameter-of-Binary-Tree (M+)
572.Subtree-of-Another-Tree (M)
549.Binary-Tree-Longest-Consecutive-Sequence-II (M)
173.Binary-Search-Tree-Iterator (M)
545.Boundary-of-Binary-Tree (H-)
272.Closest-Binary-Search-Tree-Value-II (M+)
310.Minimum-Height-Trees (H-)
331.Verify-Preorder-Serialization-of-a-Binary-Tree (H)
226.Invert-Binary-Tree (M)
655.Print-Binary-Tree (M+)
501.Find-Mode-in-Binary-Search-Tree (M+)
558.Quad-Tree-Intersection (M+)
662.Maximum-Width-of-Binary-Tree (H-)
652.Find-Duplicate-Subtrees (M)
687.Longest-Univalue-Path (M+)
742.Closest-Leaf-in-a-Binary-Tree (H)
834.Sum-of-Distances-in-Tree (H)
863.All-Nodes-Distance-K-in-Binary-Tree (H-)
954.Check-Completeness-of-a-Binary-Tree (M+)
1028.Recover-a-Tree-From-Preorder-Traversal (H-)
1339. Maximum-Product-of-Splitted-Binary-Tree (TBD)
1569.Number-of-Ways-to-Reorder-Array-to-Get-Same-BST (H)
1597.Build-Binary-Expression-Tree-From-Infix-Expression (H)

• N-ary Tree
  428.Serialize-and-Deserialize-N-ary-Tree (H)
  431.Encode-N-ary-Tree-to-Binary-Tree (H-)
  1516.Move-Sub-Tree-of-N-Ary-Tree (H-)
  1600.Throne-Inheritance (TBD)

Segment Tree

307.Range-Sum-Query-Mutable (M)
370.Range-Addition (M+)
218.The-Skyline-Problem (H)
699.Falling-Squares (H)
715.Range-Module (H)
1157.Online-Majority-Element-In-Subarray (H)
1526.Minimum-Number-of-Increments-on-Subarrays-to-Form-a-Target-Array (H-)

[Binary Index Tree]

307.Range-Sum-Query-Mutable (M)
1649.Create-Sorted-Array-through-Instructions (H)

Design

146.LRU-Cache (H-)
460.LFU Cache (H)
432.All-O-one-Data-Structure (H)
380.Insert-Delete-GetRandom-O(1) (M+)
381.Insert-Delete-GetRandom-O1-Duplicates-allowed (H-)
716.Max-Stack (M+)
355.Design-Twitter (H)
535.Encode-and-Decode-TinyURL (M)
631.Design-Excel-Sum-Formula (H)
642.Design-Search-Autocomplete-System (M+)
895.Maximum-Frequency-Stack (H)
1172.Dinner-Plate-Stacks (H)
1381.Design-a-Stack-With-Increment-Operation (H-)
1622.Fancy-Sequence (H+)

Stack

032.Longest-Valid-Parentheses (H)
155.Min-Stack (M)
225.Implement Stack using Queues (H-)
232.Implement-Queue-using-Stacks (H-)
255.Verify-Preorder-Sequence-in-Binary-Search-Tree (H)
341.Flatten-Nested-List-Iterator (M)
173.Binary-Search-Tree-Iterator (M)
536.Construct-Binary-Tree-from-String (M)
456.132-Pattern (H-)
636.Exclusive-Time-of-Functions (H-)
856.Score-of-Parentheses (M+)
946.Validate-Stack-Sequences（H-）
1190.Reverse-Substrings-Between-Each-Pair-of-Parentheses (H-)
1209.Remove-All-Adjacent-Duplicates-in-String-II (M+)
1586.Binary-Search-Tree-Iterator-II (H)

• monotonic stack
  042.Trapping-Rain-Water (H)
  084.Largest-Rectangle-in-Histogram (H)
  085.Maximal-Rectangle (H-)
  255.Verify-Preorder-Sequence-in-Binary-Search-Tree (H)
  402.Remove-K-Digits (H-)
  316.Remove-Duplicate-Letters (H)
  496.Next-Greater-Element-I (H-)
  503.Next-Greater-Element-II (H-)
  221.Maximal-Square (H-)
  739.Daily-Temperatures (H-)
  768.Max-Chunks-To-Make-Sorted-II (H-)
  901.Online-Stock-Span (H-)
  907.Sum-of-Subarray-Minimums (H)
  962.Maximum-Width-Ramp (H)
  1019.Next-Greater-Node-In-Linked-List (M)
  1063.Number-of-Valid-Subarrays (M+)
  1124.Longest-Well-Performing-Interval (H)
  1130.Minimum-Cost-Tree-From-Leaf-Values (H)
• parse expression
  071.Simplify-Path (M)
  224.Basic-Calculator(H-)
  227.Basic-Calculator-II (H-)
  772.Basic-Calculator-III (H)
  385.Mini-Parser (H)
  439.Ternary-Expression-Parser (H-)
  591.Tag-Validator (H)
  726.Number-of-Atoms (M+)
  1087.Brace-Expansion (H)
  1096.Brace-Expansion-II (H)
  1106.Parsing-A-Boolean-Expression (H-)

Deque

239.Sliding-Window-Maximum (H)
862.Shortest-Subarray-with-Sum-at-Least-K (H)
1425.Constrained-Subsequence-Sum (H)
1438.Longest-Continuous-Subarray-With-Absolute-Diff-Less-Than-or-Equal-to-Limit (H)
1499.Max-Value-of-Equation (M+)
1562.Find-Latest-Group-of-Size-M (H)

Priority Queue

004.Median-of-Two-Sorted-Arrays (H)
358.Rearrange-String-k-Distance-Apart (H-)
378.Kth-Smallest-Element-in-a-Sorted-Matrix (H-)
373.Find-K-Pairs-with-Smallest-Sums (H)
632.Smallest-Range (M)
642.Design-Search-Autocomplete-System (M+)
621.Task-Scheduler (H-)
774.Minimize-Max-Distance-to-Gas-Station (H)
1066.Campus-Bikes-II (H)
1642.Furthest-Building-You-Can-Reach (H-)

• Arrangement
  358.Rearrange-String-k-Distance-Apart (H-)
  767.Reorganize-String (M+)
  621.Task-Scheduler (H-)
  1054.Distant-Barcodes (M+)
  984.String-Without-AAA-or-BBB (M+)
  1405.Longest-Happy-String (H-)

DFS

037.Sudoku-Solver (H-)
040.Combination-Sum-II (M+)
051.N-Queens (H)
417.Pacific-Atlantic-Water-Flow (M)
200.Number-of-Islands (M)
282.Expression-Add-Operators (H)
312.Burst-Balloons (H-)
329.Longest Increasing Path in a Matrix (TBD)
399.Evaluate-Division (H-)
488.Zuma-Game (H-)
425.Word-Squares (H-)
465.Optimal-Account-Balancing (H)
803.Bricks-Falling-When-Hit (H)
959.Regions-Cut-By-Slashes (M+)
1306.Jump-Game-III (M)

• search in an array
  301.Remove-Invalid-Parentheses (H)
  473.Matchsticks-to-Square (M+)
  491.Increasing-Subsequences (M)
  698.Partition-to-K-Equal-Sum-Subsets (H-)
  996.Number-of-Squareful-Arrays (H)
  1307.Verbal-Arithmetic-Puzzle (TBD)
  1593.Split-a-String-Into-the-Max-Number-of-Unique-Substrings (M)
• memorization
  464.Can-I-Win (H)
  472.Concatenated-Words (M)
  638.Shopping-Offers (M)
  337.House-Robber-III (M+)
  403.Frog-Jump (M+)
  489.Robot-Room-Cleaner (H)
  546.Remove-Boxes (H+)
  1340.Jump-Game-V (M+)

BFS

126.Word-Ladder-II (M+)
130.Surrounded-Regions (H-)
200.Number-of-Islands (H-)
407.Trapping-Rain-Water-II (H-)
778.Swim-in-Rising-Water (H-)
529.Minesweeper (M+)
637.Average-of-Levels-in-Binary-Tree (M)
675.Cut-Off-Trees-for-Golf-Event (M)
694.Number-of-Distinct-Islands (M+)
743.Network-Delay-Time (H)
785.Is-Graph-Bipartite (M+)
815.Bus-Routes (M+)
847.Shortest-Path-Visiting-All-Nodes (H-)
864.Shortest-Path-to-Get-All-Keys (H-)
928.Minimize-Malware-Spread-II (H-)
913.Cat-and-Mouse (H+)
1036.Escape-a-Large-Maze (H)
1245.Tree-Diameter (H)
1263.Minimum-Moves-to-Move-a-Box-to-Their-Target-Location (H)
1293.Shortest-Path-in-a-Grid-with-Obstacles-Elimination (H-)
1298.Maximum-Candies-You-Can-Get-from-Boxes (M+)
1311.Get-Watched-Videos-by-Your-Friends (M)
1345.Jump-Game-IV (M+)
1368.Minimum-Cost-to-Make-at-Least-One-Valid-Path-in-a-Grid (H)
1559.Detect-Cycles-in-2D-Grid (M)
1568.Minimum-Number-of-Days-to-Disconnect-Island (H-)
1617.Count-Subtrees-With-Max-Distance-Between-Cities (H-)

• 拓扑排序
  207.Course-Schedule (H-)
  210.Course-Schedule-II (M)
  269.Alien-Dictionary (H-)
  310.Minimum-Height-Trees (H-)
  802.Find-Eventual-Safe-States (H-)
  1136.Parallel-Courses (M)
  1203.Sort-Items-by-Groups-Respecting-Dependencies (H)
  1462.Course-Schedule-IV (M)
  1591.Strange-Printer-II (H-)

Trie

208.Implement-Trie--Prefix-Tree (M+)
211.Add-and-Search-Word (H-)
421.Maximum XOR of Two Numbers in an Array (H)
648.Replace-Words (H)
588.Design-In-Memory-File-System (H-)
677.Map-Sum-Pairs (M)
676.Implement-Magic-Dictionary (H-)
212.Word-Search-II (H-)
745.Prefix-and-Suffix-Search (H-)
1268.Search-Suggestions-System (H-)
1032. Stream of Characters (TBD)

Greedy

055.Jump-Game (E+)
045.Jump-Game-II (M)
084.Largest-Rectangle-in-Histogram (H)
085.Maximal-Rectangle (H)
134.Gas-Station (H)
221.Maximal-Square (H)
239.Sliding-Window-Maximum (H)
300.Longest-Increasing-Subsequence (M+)
334.Increasing-Triplet-Subsequence (H-)
354.Russian-Doll-Envelopes
316.Remove Duplicate Letters (H)
229.Majority-Element-II (H)
659.Split-Array-into-Consecutive-Subsequences (H-)
484.Find-Permutation (H)
386.Lexicographical-Numbers (H)
440.K-th-Smallest-in-Lexicographical-Order (H)
621.Task-Scheduler (H-)
624.Maximum-Distance-in-Arrays (M)
665.Non-decreasing-Array (H-)
670.Maximum-Swap (M+)
321.Create-Maximum-Number (H)
135.Candy (M+)
649.Dota2-Senate (H)
330.Patching-Array (H)
650.2-Keys-Keyboard (M+)
683.K-Empty-Slots　(H)
517.Super-Washing-Machines (H)
757.Set-Intersection-Size-At-Least-Two （H）
826.Most-Profit-Assigning-Work (M)
857.Minimum-Cost-to-Hire-K-Workers (H)
871.Minimum-Number-of-Refueling-Stops (H-)
881.Boats-to-Save-People (H-)
910.Smallest-Range-II (M+)
936.Stamping-The-Sequence (H)
948.Bag-of-Tokens (M+)
968.Binary-Tree-Cameras (H)
995.Minimum-Number-of-K-Consecutive-Bit-Flips (H-)
1040.Moving-Stones-Until-Consecutive-II (H)
1121.Divide Array Into Increasing Sequences (TBD)
1191.K-Concatenation-Maximum-Sum (M+)
1253.Reconstruct-a-2-Row-Binary-Matrix (M)
1402.Reducing-Dishes (M)
1488.Avoid-Flood-in-The-City (H-)
1505.Minimum-Possible-Integer-After-at-Most-K-Adjacent-Swaps-On-Digits (H)
1526.Minimum-Number-of-Increments-on-Subarrays-to-Form-a-Target-Array (H-)
1535.Find-the-Winner-of-an-Array-Game (M+)
1536.Minimum-Swaps-to-Arrange-a-Binary-Grid (H-)
1564.Put-Boxes-Into-the-Warehouse-I (M+)
1578.Minimum-Deletion-Cost-to-Avoid-Repeating-Letters (M)
1585.Check-If-String-Is-Transformable-With-Substring-Sort-Operations (H)

• Sort+PQ
  502.IPO （H-）
  630.Course-Schedule-III (H)
  1353.Maximum-Number-of-Events-That-Can-Be-Attended (TBD)
• Parenthesis
  921.Minimum-Add-to-Make-Parentheses-Valid (M+)
  1249.Minimum-Remove-to-Make-Valid-Parentheses (M+)
  1541.Minimum-Insertions-to-Balance-a-Parentheses-String (M+)
  678.Valid-Parenthesis-String (H-)
• Intervals
  1288.Remove Covered Intervals (TBD)

Linked List

061.Rotate-List (M)
086.Partition-List (M)
142.Linked-List-Cycle-II (M+)
109.Convert-Sorted-List-to-Binary-Search-Tree (M)
092.Reverse-Linked-List-II (H-)
143.Reorder-List (H-)
369.Plus-One-Linked-List (M)
430.Flatten-a-Multilevel-Doubly-Linked-List (H-)
457.Circular-Array-Loop (H-)
708.Insert-into-a-Cyclic-Sorted-List (H-)
1474.Delete-N-Nodes-After-M-Nodes-of-a-Linked-List (M+)

Dynamic Programming

264.Ugly-Number-II (M+)
265.Paint-House-II (H)
139.Word-Break (M+)
091.Decode-Ways (M)
639.Decode-Ways-II (H)
629.K-Inverse-Pairs-Array (H)
634.Find-the-Derangement-of-An-Array (H)
221.Maximal-Square (H-)
1277.Count-Square-Submatrices-with-All-Ones (M+)
600.Non-negative-Integers-without-Consecutive-Ones (H)
656.Coin-Path (H-)
053.Maximum-Subarray (E+)
152.Maximum-Product-Subarray (M+)
818.Race-Car (H)
377.Combination-Sum-IV (M)
132.Palindrome-Partitioning-II (H-)
837.New-21-Game (H-)
887.Super-Egg-Drop (H)
920.Number-of-Music-Playlists (H)
940.Distinct-Subsequences-II (H)
446.Arithmetic-Slices-II-Subsequence (H-)
1027.Longest-Arithmetic-Sequence (M+)
1269.Number-of-Ways-to-Stay-in-the-Same-Place-After-Some-Steps (M+)
1316.Distinct-Echo-Substrings (M+)
1420.Build-Array-Where-You-Can-Find-The-Maximum-Exactly-K-Comparisons (H-)
1444. Number of Ways of Cutting a Pizza (TBD)
1531.String-Compression-II (H+)
1575.Count-All-Possible-Routes (M+)
1621.Number-of-Sets-of-K-Non-Overlapping-Line-Segments (H)
1638.Count-Substrings-That-Differ-by-One-Character (M+)
1639.Number-of-Ways-to-Form-a-Target-String-Given-a-Dictionary (H-)

• 基本型 I
  198.House-Robber (E)
  213.House-Robber-II (M+)
  1388.Pizza-With-3n-Slices (H-)
  276.Paint-Fence (H-)
  376.Wiggle-Subsequence (H-)
  487.Max-Consecutive-Ones-II (H-)
  123.Best-Time-to-Buy-and-Sell-Stock-III (M+)
  188.Best-Time-to-Buy-and-Sell-Stock-IV (H)
  309.Best-Time-to-Buy-and-Sell-Stock-with-Cooldown (H-)
  714.Best-Time-to-Buy-and-Sell-Stock-with-Transaction-Fee (M+)
  514.Freedom-Trail (H-)
  740.Delete-and-Earn (H-)
  552.Student-Attendance-Record-II (H)
  801.Minimum-Swaps-To-Make-Sequences-Increasing (M)
  903.Valid-Permutations-for-DI-Sequence (H)
  1186.Maximum-Subarray-Sum-with-One-Deletion (H-)
  1187.Make-Array-Strictly-Increasing (H-)
  1223.Dice-Roll-Simulation (H-)
  1419.Minimum-Number-of-Frogs-Croaking (M)
  1548.The-Most-Similar-Path-in-a-Graph (M+)
• 基本型 II
  368.Largest-Divisible-Subset (M+)
  300.Longest-Increasing-Subsequence (M+)
  673.Number-of-Longest-Increasing-Subsequence (M+)
  983.Minimum-Cost-For-Tickets (H-)
  1043.Partition-Array-for-Maximum-Sum(M+)
  1105.Filling-Bookcase-Shelves (H-)
  1546.Maximum-Number-of-Non-Overlapping-Subarrays-With-Sum-Equals-Target (M+)
  1626.Best-Team-With-No-Conflicts (M)
• 走迷宫型
  174.Dungeon-Game (H-)
  741.Cherry-Pickup (H-)
  1463.Cherry-Pickup-II (M)
  576.Out-of-Boundary-Paths (H)
  931.Minimum-Falling-Path-Sum (M)
  1289.Minimum-Falling-Path-Sum-II (M+)
  1301.Number-of-Paths-with-Max-Score (M+)
  1594.Maximum-Non-Negative-Product-in-a-Matrix (M)
• 背包型
  322.Coin-Change (M)
  416.Partition-Equal-Subset-Sum (M+)
  518.Coin-Change-2 (H-)
  474.Ones-and-Zeroes (H-)
  494.Target-Sum (M+)
  805.Split-Array-With-Same-Average (H)
  879.Profitable-Schemes (M+)
  956.Tallest-Billboard (H)
  1049.Last-Stone-Weight-II (H-)
  1449.Form-Largest-Integer-With-Digits-That-Add-up-to-Target (H-)
• 键盘型
  650.2-Keys-Keyboard (M+)
  651.4-Keys-Keyboard (M+)
  935.Knight-Dialer (M)
  1320.Minimum-Distance-to-Type-a-Word-Using-Two-Fingers (H)
• 区间型 I
  410.Split-Array-Largest-Sum (H)
  813.Largest-Sum-of-Averages (H-)
  1278.Palindrome-Partitioning-III (H)
  1335.Minimum-Difficulty-of-a-Job-Schedule (M+)
  1478.Allocate-Mailboxes (H)
• 区间型 II
  312.Burst-Balloons (H-)
  375.Guess-Number-Higher-or-Lower-II (H)
  516.Longest-Palindromic-Subsequence (H-)
  546.Remove-Boxes (H+)
  664.Strange-Printer (H)
  730.Count-Different-Palindromic-Subsequences (H)
  1000.Minimum-Cost-to-Merge-Stones (H)
  1130.Minimum-Cost-Tree-From-Leaf-Values (M+)
  1246.Palindrome-Removal (H)
  1039.Minimum-Score-Triangulation-of-Polygon (H)
  1547.Minimum-Cost-to-Cut-a-Stick (M)
• 双序列型
  010.Regular-Expression-Matching (H)
  044.Wildcard-Matching (H-)
  097.Interleaving-String (H-)
  072.Edit-Distance (H-)
  115.Distinct-Subsequences (H-)
  583.Delete-Operation-for-Two-Strings (M+)
  712.Minimum-ASCII-Delete-Sum-for-Two-Strings (M+)
  718.Maximum-Length-of-Repeated-Subarray (M)
  727.Minimum-Window-Subsequence (H-)
  1035.Uncrossed-Lines (M)
  1092.Shortest-Common-Supersequence (H-)
  1143.Longest-Common-Subsequence (M)
  1216.Valid-Palindrome-III (M+)
  1312.Minimum-Insertion-Steps-to-Make-a-String-Palindrome (M+)
  1458.Max-Dot-Product-of-Two-Subsequences (M)
• 状态压缩DP
  691.Stickers-to-Spell-Word (H)
  943.Find-the-Shortest-Superstring (H+)
  1125.Smallest-Sufficient-Team (H)
  1349.Maximum-Students-Taking-Exam (H)
  1411.Number-of-Ways-to-Paint-N×3-Grid (M)
  1434.Number-of-Ways-to-Wear-Different-Hats-to-Each-Other (H-)
  1494.Parallel-Courses-II (H)
  1595.Minimum-Cost-to-Connect-Two-Groups-of-Points (H)
• Catalan
  096.Unique-Binary-Search-Trees (M+)
  1259.Handshakes-That-Don't-Cross (M+)

Bit Manipulation

136.Single-Number (M)
137.Single-Number-II (H-)
260.Single-Number-III (H)
371.Sum-of-Two-Integers (H)
318.Maximum-Product-of-Word-Lengths (M+)
342.Power-of-Four (H)
957.Prison-Cells-After-N-Days (H)
1461.Check-If-a-String-Contains-All-Binary-Codes-of-Size-K (TBD)
1521.Find-a-Value-of-a-Mysterious-Function-Closest-to-Target (H-)

• XOR
  1310.XOR Queries of a Subarray (TBD)
  1442.Count Triplets That Can Form Two Arrays of Equal XOR (TBD)
  1506.Find-Root-of-N-Ary-Tree (M+)
• Bit Mask
  1601.Maximum-Number-of-Achievable-Transfer-Requests (H-)

Divide and Conquer

315.Count-of-Smaller-Numbers-After-Self (H-)
327.Count-of-Range-Sum (H-)
493.Reverse-Pairs (M+)
1649.Create-Sorted-Array-through-Instructions (H)

String

005.Longest-Palindromic-Substring (H)
006.ZigZag-Conversion (M+)
336.Palindrome-Pairs (H-)
388.Longest-Absolute-File-Path (M+)
408.Valid-Word-Abbreviation (M)
411.Minimum-Unique-Word-Abbreviation (H)
418.Sentence-Screen-Fitting (M+)
527.Word-Abbreviation (M+)
647.Palindromic-Substrings (M+)
556.Next Greater Element III (H-)
616.Add-Bold-Tag-in-String (M)
467.Unique-Substrings-in-Wraparound-String (H-)
564.Find-the-Closest-Palindrome (H)
722.Remove-Comments (H)
736.Parse-Lisp-Expression (H-)
844.Backspace-String-Compare (M+)
1616.Split-Two-Strings-to-Make-Palindrome (M+)

• Rolling Hash
  1044.Longest-Duplicate-Substring (H)
  1062.Longest-Repeating-Substring (H-)
  1554.Strings-Differ-by-One-Character (H)
• KMP
  028.Implement-strStr (H)
  214.Shortest-Palindrome (H)
  459.Repeated-Substring-Pattern (TBD)
  1392.Longest-Happy-Prefix (H)
  1410.HTML-Entity-Parser (TBD)

Sort

041.First-Missing-Positive (H)
164.Maximum-Gap (H)
179.Largest-Number (H-)
581.shortest-unsorted-continuous-subarray (M+)
275.H-Index-II (M+)
406.Queue-Reconstruction-by-Height (M+)
442.Find-All-Duplicates-in-an-Array (M+)
448.Find-All-Numbers-Disappeared-in-an-Array (M+)
731.My-Calendar-II (M+)
452.Minimum-Number-of-Arrows-to-Burst-Balloons (H-)
435.Non-overlapping-Intervals (M+)
1024.Video-Stitching (M+)
1326.Minimum-Number-of-Taps-to-Open-to-Water-a-Garden (TBD)
1235.Maximum-Profit-in-Job-Scheduling (H-)
1268.Search-Suggestions-System (H-)
1520.Maximum-Number-of-Non-Overlapping-Substrings (H-)

• Sweep Line
  252.Meeting-Rooms (M)
  253.Meeting-Rooms-II (M+)
  056.Merge-Intervals (M)
  057.Insert-Intervals (M)
  732.My-Calendar-III (M)
  759.Employee-Free-Time (M+)
  1589.Maximum-Sum-Obtained-of-Any-Permutation (M)

Union Find

547.Friend-Circles (M)
200.Number-of-Islands (H-)
305.Number-of-Islands-II (H-)
130.Surrounded-Regions (H-)
128.Longest-Consecutive-Sequence (H-)
684.Redundant-Connection (M)
685.Redundant-Connection-II (H)
721.Accounts-Merge (M+)
765.Couples-Holding-Hands (H-)
785.Is-Graph-Bipartite (M+)
924.Minimize-Malware-Spread (H-)
947.Most-Stones-Removed-with-Same-Row-or-Column (M+)
952.Largest-Component-Size-by-Common-Factor (H)
959.Regions-Cut-By-Slashes (H-)
990.Satisfiability-of-Equality-Equations (M+)
1101.The-Earliest-Moment-When-Everyone-Become-Friends (M+)
1202.Smallest-String-With-Swaps (M+)
1319.Number-of-Operations-to-Make-Network-Connected (M+)
1627.Graph-Connectivity-With-Threshold (M+)
1632.Rank-Transform-of-a-Matrix (H)
1631.Path-With-Minimum-Effort (H-)

• MST
  1135.Connecting-Cities-With-Minimum-Cost　(M+)
  1168.Optimize-Water-Distribution-in-a-Village (H-)
  1489.Find-Critical-and-Pseudo-Critical-Edges-in-Minimum-Spanning-Tree (H)
  1579.Remove-Max-Number-of-Edges-to-Keep-Graph-Fully-Traversable (H-)
  1584.Min-Cost-to-Connect-All-Points (H-)

Recursion

133.Clone-Graph (M+)
213.House-Robber-II (H-)
241.Different-Ways-to-Add-Parentheses (H-)
390.Elimination-Game (H)
395.Longest-Substring-with-At-Least-K-Repeating-Characters (H)
397.Integer-Replacement (M+)
679.24-Game (H)
761.Special-Binary-String (H)
779.K-th-Symbol-in-Grammar (M)
780.Reaching-Points (H-)
808.Soup-Servings (H)
880.Decoded-String-at-Index (H-)
902.Numbers-At-Most-N-Given-Digit-Set (M)
932.Beautiful-Array (H-)
964.Least-Operators-to-Express-Number (H)
991.Broken-Calculator (M)
1088.Confusing-Number-II (H)
1274.Number-of-Ships-in-a-Rectangle (M)
1545. Find Kth Bit in Nth Binary String (TBD)
1553.Minimum-Number-of-Days-to-Eat-N-Oranges (H)
1611.Minimum-One-Bit-Operations-to-Make-Integers-Zero (H)

• Min-Max Strategy
  877.Stone-Game (M+) (aka. 486.Predict-the-Winner)
  1140.Stone-Game-II (M)
  1406.Stone-Game-III (M+)
  1510.Stone-Game-IV (M)
  1563.Stone-Game-V (H-)

Graph

332.Reconstruct-Itinerary (H)
753.Cracking-the-Safe (H)
787.Cheapest-Flights-Within-K-Stops (H-)
1192.Critical-Connections-in-a-Network (H)
1334.Find-the-City-With-the-Smallest-Number-of-Neighbors-at-a-Threshold-Distance (TBD)
1361.Validate-Binary-Tree-Nodes (TBD)
1514.Path-with-Maximum-Probability (H)

Math

089.Gray-Code (M+) (aka. 1238. Circular Permutation in Binary Representation)
233.Number-of-Digit-One (H-)
335.Self-Crossing (H)
365.Water-and-Jug-Problem (H)
343.Integer-Break (M)
458.Poor-Pigs (H)
400.n-th-digit (M)
441.Arranging-Coins (M-)
628.Maximum-Product-of-Three-Numbers (M)
672.Bulb-Switcher-II (H)
754.Reach-a-Number (H)
829.Consecutive-Numbers-Sum (M)
878.Nth-Magical-Number (M+)
883.Projection-Area-of-3D-Shapes (E+)
891.Sum-of-Subsequence-Widths (M+)
899.Orderly-Queue (M)
963.Minimum-Area-Rectangle-II (H-)
964.Least-Operators-to-Express-Number (H)
972.Equal-Rational-Numbers (H)
1012.Numbers-With-Repeated-Digits (H-)
1017.Convert-to-Base--2 (M+)
1073.Adding-Two-Negabinary-Numbers (H-)
1025.Divisor-Game (M)
1040.Moving-Stones-Until-Consecutive-II (H)
1015.Smallest-Integer-Divisible-by-K (M+)
1103.Distribute-Candies-to-People (M+)
1330.Reverse-Subarray-To-Maximize-Array-Value (TBD)
1250.Check-If-It-Is-a-Good-Array (M+)
1605.Find-Valid-Matrix-Given-Row-and-Column-Sums (M+)

• Distances
  296.Best-Meeting-Point (M+)
  1131.Maximum-of-Absolute-Value-Expression (H)
  1515.Best Position for a Service Centre (TBD)
• Geometry
  223.Rectangle-Area (M+)
  1401.Circle-and-Rectangle-Overlapping (H)
  1453.Maximum-Number-of-Darts-Inside-of-a-Circular-Dartboard (H)
  1610.Maximum-Number-of-Visible-Points (H)
• Random Pick
  382.Linked-List-Random-Node (H)
  470.Implement-Rand10()-Using-Rand7() (M+)
  478.Generate-Random-Point-in-a-Circle (H-)
  497.Random-Point-in-Non-overlapping-Rectangles (M+)
  519.Random-Flip-Matrix (H-)
  528.Random-Pick-with-Weight (H-)
  710.Random-Pick-with-Blacklist (M+)
  1227.Airplane-Seat-Assignment-Probability (M+)
• Combinatorics
  046.Permutations (M+)
  047.Permutations-II (H)
  060.Permutation-Sequence (H)
  077.Combinations (H-)
  1286.Iterator-for-Combination (M+)
  1359.Count-All-Valid-Pickup-and-Delivery-Options (M+)
  1467.Probability-of-a-Two-Boxes-Having-The-Same-Number-of-Distinct-Balls (H-)
  1641.Count-Sorted-Vowel-Strings (M+)
  1643.Kth-Smallest-Instructions (M+)

Brute Force  

1625.Lexicographically-Smallest-String-After-Applying-Operations (H-)

Others  

007.Reverse-Integer (M)
048.Rotate-Image (M+)
065.Valid-Number (H-)
158.Read-N-Characters-Given-Read4-II-Call-multiple-times　(H)
240.Search-a-2D-Matrix-II (M+)
277.Find-the-Celebrity (H-)
311.Sparse-Matrix-Multiplication (M)
324.Wiggle-Sort-II (M)
593.Valid-Square (H)
168.Excel-Sheet-Column-Title (H)
453.Minimum-Moves-to-Equal-Array-Elements (M)
587.Erect-the-Fence (H)
087.Scramble-String (H)
391.Perfect-Rectangle (H)
645.Set-Mismatch (H)
423.Reconstruct-Original-Digits-from-English (H-)
335.Self-Crossing (H)
479.Largest-Palindrome-Product (M+)
689.Maximum-Sum-of-3-Non-Overlapping-Subarrays (M+)
782.Transform-to-Chessboard (H+)
466.Count-The-Repetitions (H)
810.Chalkboard-XOR-Game (H)
420.Strong-Password-Checker (H)
850.Rectangle-Area-II (H-)
775.Global-and-Local-Inversions (M)
794.Valid-Tic-Tac-Toe-State (M+)
798.Smallest-Rotation-with-Highest-Score (H)
825.Friends-Of-Appropriate-Ages (M+)
835.Image-Overlap (H)
843.Guess-the-Word (M)
855.Exam-Room (M+)
858.Mirror-Reflection (H)
866.Prime-Palindrome (H-)
918.Maximum-Sum-Circular-Subarray (H-)
906.Super-Palindromes (H-)
927.Three-Equal-Parts (M)
1067.Digit-Count-in-Range (H)
1109.Corporate-Flight-Bookings (M)
1183.Maximum-Number-of-Ones (H)
1262.Greatest-Sum-Divisible-by-Three (TBD)
1267.Count-Servers-that-Communicate (M+)
1272.Remove-Interval (TBD)
1284.Minimum-Number-of-Flips-to-Convert-Binary-Matrix-to-Zero-Matrix (TBD)
1352.Product-of-the-Last-K-Numbers (TBD)
1354.Construct-Target-Array-With-Multiple-Sums (TBD)
1262.Greatest-Sum-Divisible-by-Three (TBD)
1363.Largest-Multiple-of-Three (TBD)
1452.People-Whose-List-of-Favorite-Companies-Is-Not-a-Subset-of-Another-List (TBD)
1538.Guess-the-Majority-in-a-Hidden-Array (M+)
1539.Kth Missing Positive Number (TBD)
1540.Can Convert String in K Moves (TBD)

Templates  

Math_Pow
Binary_Index_Tree
Inverse_Element
Graph
Bit_Manipulation
Combination-Number
RB_Tree