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LeetCode — Complete Study Plan Coverage

249 self-tested Java solutions in `pkg5leetcode`. Each file compiles and runs with built-in assertions.

powershell
1# One file2java pkg5leetcode/blind75/blind75_LC1TwoSum.java3 4# All LeetCode (smoke test — takes several minutes)5./run-leetcode-all.ps1

Study plan tracks

Track Folder Problems Source
Quick start pkg5leetcode/ (root) 12 Curated pattern intro
Blind 75 blind75/ 75 Blind / NeetCode 75
LeetCode 75 official75/ 75 leetcode.com/studyplan/leetcode-75
Interview 150 interview150/ 62 Extras from Top Interview 150 not in Blind 75
Top 100 Liked top100/ 25 Extras from Top 100 Liked

Note: Official LeetCode 75 and Blind 75 are different lists. Blind 75 focuses on classic interview patterns (Two Sum, 3Sum, Course Schedule). Official LC75 focuses on trending essentials (Merge Strings Alternately, Asteroid Collision, Dota2 Senate). Do both.

Blind 75 index (`blind75/`)

Category LC # File prefix
Array 1, 121, 217, 238, 53, 152, 153, 33, 15, 11 blind75_LC*
Binary 371, 191, 338, 268, 190
DP 70, 322, 300, 1143, 139, 39, 198, 213, 91, 62, 55
Graph 133, 207, 417, 200, 128, 269*, 261*, 323* *premium
Interval 57, 56, 435, 252*, 253*
Linked List 206, 141, 21, 23, 19, 143
Matrix 73, 54, 48, 79
String 3, 424, 76, 242, 49, 20, 125, 5, 647, 271*
Tree 104, 100, 226, 124, 102, 297, 572, 105, 98, 230, 235, 208, 211, 212
Heap 347, 295

Official LeetCode 75 topics (`official75/`)

Topic Example problems
Array / String 1768, 1071, 1431, 605, 151, 443, 238, 334
Two Pointers 283, 392, 11, 1679
Sliding Window 643, 1456, 1004, 1493
Prefix Sum 1732, 724
Hash Map / Set 2215, 1207, 1657, 2352
Stack 2390, 735, 394
Queue 933, 649
Linked List 2095, 206, 2130, 328
Tree DFS 104, 872, 1448, 1372, 437, 236
Tree BFS 199, 1161
BST 700, 450
Graph DFS 841, 797, 1466, 399
Graph BFS 1926, 994
Heap / PQ 215, 502, 373, 2336
Binary Search 374, 230, 162, 74
Backtracking 17, 216
DP 1D 746, 790, 714, 72
DP Multidim 123, 188, 221, 63
Bit Manipulation 338, 1318, 2419
Trie 208, 1268
Intervals 435, 452
Monotonic Stack 739, 901

Interview 150 extras (`interview150/` — 62 problems)

Problems from Top Interview 150 not in Blind 75, including: 2, 4, 7, 9, 14, 26, 27, 35, 36, 42, 45, 58, 66, 69, 74, 83, 88, 94, 101, 118, 136, 146, 150, 155, 167, 173, 189, 202, 205, 219, 234, 287, 290, 344, 383, 399, 409, 438, 509, 560, 704, 733, 746, 739, 763, 767, 787, 844, 852, 875, 876, 977, 989, 994, 1004, 116, 120, 134, 236, 283, …

Top 100 liked extras (`top100/` — 25 problems)

Famous liked problems not in Blind 75 or Interview 150 extras, including: 17, 22, 31, 34, 46, 51, 64, 72, 75, 78, 84, 85, 86, 96, 114, 148, 215, 222, 239, 240, 448, 461, 494, 503, 516, …

Root starter set (12)

File LC Pattern
leetcode1TwoSum 1 Hashing
leetcode2ValidParentheses 20 Stack
leetcode3ValidAnagram 242 Counting
leetcode4BestTimeToBuySellStock 121 Greedy
leetcode5MaxSubArray 53 Kadane
leetcode6ProductExceptSelf 238 Prefix/suffix
leetcode7LongestSubstringNoRepeat 3 Sliding window
leetcode8MergeIntervals 56 Intervals
leetcode9ReverseLinkedList 206 Linked list
leetcode10ClimbingStairs 70 DP
leetcode11NumberOfIslands 200 DFS
leetcode12TopKFrequent 347 Heap

Patterns you must master

  1. Hashing · 2. Two pointers · 3. Sliding window · 4. Binary search · 5. Stack
  2. Linked list · 7. Trees (DFS/BFS) · 8. Graphs · 9. Heap / Top-K · 10. Backtracking
  3. Dynamic programming · 12. Greedy / intervals · 13. Bit manipulation · 14. Trie

How to practice

  1. Read problem on LeetCode (link from LC number).
  2. Solve on paper / whiteboard first.
  3. Compare with solution here; re-implement from memory.
  4. Run the file — all tests passed means your re-implementation matches.
  5. State time/space complexity out loud.

See Interview Guide for the full interview framework.

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