leetcode-textbook

The 100-Problem Map

The complete curriculum. Each row is one problem in this book. Patterns are ordered easiest-first; within each pattern, problems ramp from Easy to Medium.

Pattern 1 - Arrays & Hashing (8 problems)

# LC Problem Difficulty
1 217 Contains Duplicate Easy
2 242 Valid Anagram Easy
3 1 Two Sum Easy
4 49 Group Anagrams Medium
5 347 Top K Frequent Elements Medium
6 238 Product of Array Except Self Medium
7 36 Valid Sudoku Medium
8 128 Longest Consecutive Sequence Medium

Pattern 2 - Two Pointers (6 problems)

# LC Problem Difficulty
9 125 Valid Palindrome Easy
10 167 Two Sum II - Input Array Is Sorted Medium
11 15 3Sum Medium
12 11 Container With Most Water Medium
13 977 Squares of a Sorted Array Easy
14 283 Move Zeroes Easy

Pattern 3 - Sliding Window (6 problems)

# LC Problem Difficulty
15 121 Best Time to Buy and Sell Stock Easy
16 3 Longest Substring Without Repeating Characters Medium
17 424 Longest Repeating Character Replacement Medium
18 76 Minimum Window Substring Hard* (kept as window capstone)
19 209 Minimum Size Subarray Sum Medium
20 219 Contains Duplicate II Easy

*Problem 18 (Min Window Substring) is officially Hard on LeetCode but is the canonical sliding-window teaching problem, so it is included as the section capstone. All other problems are Easy/Medium.

Pattern 4 - Stack (5 problems)

# LC Problem Difficulty
21 20 Valid Parentheses Easy
22 155 Min Stack Medium
23 150 Evaluate Reverse Polish Notation Medium
24 739 Daily Temperatures Medium
25 22 Generate Parentheses Medium

Pattern 5 - Binary Search (7 problems)

# LC Problem Difficulty
26 704 Binary Search Easy
27 35 Search Insert Position Easy
28 278 First Bad Version Easy
29 74 Search a 2D Matrix Medium
30 875 Koko Eating Bananas Medium
31 153 Find Minimum in Rotated Sorted Array Medium
32 33 Search in Rotated Sorted Array Medium

Pattern 6 - Linked List (7 problems)

# LC Problem Difficulty
33 206 Reverse Linked List Easy
34 21 Merge Two Sorted Lists Easy
35 143 Reorder List Medium
36 19 Remove Nth Node From End of List Medium
37 141 Linked List Cycle Easy
38 2 Add Two Numbers Medium
39 234 Palindrome Linked List Easy

Pattern 7 - Trees (9 problems)

# LC Problem Difficulty
40 226 Invert Binary Tree Easy
41 104 Maximum Depth of Binary Tree Easy
42 100 Same Tree Easy
43 110 Balanced Binary Tree Easy
44 543 Diameter of Binary Tree Easy
45 102 Binary Tree Level Order Traversal Medium
46 235 Lowest Common Ancestor of a BST Medium
47 98 Validate Binary Search Tree Medium
48 230 Kth Smallest Element in a BST Medium

Pattern 8 - Tries (4 problems)

# LC Problem Difficulty
49 208 Implement Trie (Prefix Tree) Medium
50 211 Design Add and Search Words Data Structure Medium
51 212 Word Search II Hard* (trie capstone)
52 720 Longest Word in Dictionary Easy

*Problem 51 is officially Hard but is the canonical trie + backtracking teaching problem.

Pattern 9 - Heap / Priority Queue (5 problems)

# LC Problem Difficulty
53 703 Kth Largest Element in a Stream Easy
54 215 Kth Largest Element in an Array Medium
55 347* Top K Frequent Elements Medium
56 973 K Closest Points to Origin Medium
57 355 Design Twitter Medium

*Problem 55 (LC 347) also appears in Pattern 1 because it teaches both hashing and heap. Here it is solved with a heap. To avoid a duplicate folder, the heap version lives in patterns/09-heap/0347-top-k-frequent-heap/.

Pattern 10 - Backtracking (6 problems)

# LC Problem Difficulty
58 78 Subsets Medium
59 39 Combination Sum Medium
60 46 Permutations Medium
61 90 Subsets II Medium
62 79 Word Search Medium
63 17 Letter Combinations of a Phone Number Medium

Pattern 11 - Graphs (9 problems)

# LC Problem Difficulty
64 200 Number of Islands Medium
65 133 Clone Graph Medium
66 695 Max Area of Island Medium
67 994 Rotting Oranges Medium
68 207 Course Schedule Medium
69 417 Pacific Atlantic Water Flow Medium
70 130 Surrounded Regions Medium
71 733 Flood Fill Easy
72 684 Redundant Connection Medium

Pattern 12 - Greedy (6 problems)

# LC Problem Difficulty
73 53 Maximum Subarray Medium
74 55 Jump Game Medium
75 45 Jump Game II Medium
76 134 Gas Station Medium
77 846 Hand of Straights Medium
78 11* Container With Most Water Medium

*Problem 78 (LC 11) also appears in Pattern 2 (two pointers). It is the canonical greedy/two- pointer overlap. The greedy folder version is patterns/12-greedy/0011-container-greedy/.

Pattern 13 - Intervals (4 problems)

# LC Problem Difficulty
79 56 Merge Intervals Medium
80 57 Insert Interval Medium
81 435 Non-overlapping Intervals Medium
82 252 Meeting Rooms Easy

Pattern 14 - 1-D Dynamic Programming (8 problems)

# LC Problem Difficulty
83 70 Climbing Stairs Easy
84 746 Min Cost Climbing Stairs Easy
85 198 House Robber Medium
86 213 House Robber II Medium
87 322 Coin Change Medium
88 300 Longest Increasing Subsequence Medium
89 139 Word Break Medium
90 5 Longest Palindromic Substring Medium

Pattern 15 - 2-D Dynamic Programming (7 problems)

# LC Problem Difficulty
91 62 Unique Paths Medium
92 1143 Longest Common Subsequence Medium
93 64 Minimum Path Sum Medium
94 518 Coin Change II Medium
95 72 Edit Distance Medium
96 647 Palindromic Substrings Medium
97 416 Partition Equal Subset Sum Medium

Pattern 16 - Bit Manipulation (3 problems)

# LC Problem Difficulty
98 136 Single Number Easy
99 191 Number of 1 Bits Easy
100 268 Missing Number Easy

Summary

This map drives the subagent generation. Each pattern = one subagent batch.