Your complete DSA curriculum
355 problems. 26 patterns. One executable plan.
● Master list implemented
● 8 day streak
DKComplete pattern-first curriculum
Every problem from the master list, organized to execute
Work the priority 50 first, expand by pattern, then close with the hard set and company-specific review. Progress is saved on this device.
0%
0 solvedof 355 unique problems
355Unique problemsDeduplicated across patterns
26Topic playbooksOptimized Python templates
50Highest priorityYour foundation sequence
30Hard setSenior-loop readiness
Implementation checklist
26 topics355 problems in view
1
Two Sum
CorePriority #1
49
Group Anagrams
CorePriority #2
238
Product of Array Except Self
CorePriority #3
128
Longest Consecutive Sequence
CorePriority #4Also: Union-Find / Disjoint Set Union
560
Subarray Sum Equals K
VariationPriority #10Also: Prefix Sum and Difference Array
36
Valid Sudoku
CoreAlso: Matrix and Simulation
41
First Missing Positive
VariationHard set
169
Majority Element
Core
217
Contains Duplicate
Core
242
Valid Anagram
Core
299
Bulls and Cows
Variation
347
Top K Frequent Elements
CoreAlso: Heap and Priority Queue
380
Insert Delete GetRandom O(1)
VariationAlso: Data Structure Design
448
Find All Numbers Disappeared in an Array
Core
454
4Sum II
Variation
525
Contiguous Array
VariationAlso: Prefix Sum and Difference Array
974
Subarray Sums Divisible by K
VariationAlso: Prefix Sum and Difference Array
2013
Detect Squares
VariationAlso: Data Structure Design
15
3Sum
CorePriority #5
11
Container With Most Water
CorePriority #6Also: Greedy Algorithms
18
4Sum
Variation
26
Remove Duplicates from Sorted Array
Core
31
Next Permutation
Variation
42
Trapping Rain Water
CoreHard setAlso: Monotonic Stack and Monotonic Queue
75
Sort Colors
Variation
80
Remove Duplicates from Sorted Array II
Variation
125
Valid Palindrome
Core
167
Two Sum II – Input Array Is Sorted
Core
283
Move Zeroes
Core
408
Valid Word Abbreviation
Variation
680
Valid Palindrome II
Core
844
Backspace String Compare
Core
881
Boats to Save People
VariationAlso: Greedy Algorithms
977
Squares of a Sorted Array
Core
3
Longest Substring Without Repeating Characters
CorePriority #7
424
Longest Repeating Character Replacement
CorePriority #8
76
Minimum Window Substring
CorePriority #9Hard set
30
Substring with Concatenation of All Words
Advanced
121
Best Time to Buy and Sell Stock
CoreAlso: Stock and State-Machine DP
209
Minimum Size Subarray Sum
Core
239
Sliding Window Maximum
AdvancedHard setAlso: Monotonic Stack and Monotonic Queue
438
Find All Anagrams in a String
Core
567
Permutation in String
Core
713
Subarray Product Less Than K
Core
862
Shortest Subarray with Sum at Least K
AdvancedAlso: Monotonic Stack and Monotonic Queue
904
Fruit Into Baskets
Core
992
Subarrays with K Different Integers
Advanced
1004
Max Consecutive Ones III
Core
1438
Longest Continuous Subarray With Absolute Diff ≤ Limit
Advanced
303
Range Sum Query – Immutable
Core
304
Range Sum Query 2D – Immutable
Core
523
Continuous Subarray Sum
Core
724
Find Pivot Index
Core
930
Binary Subarrays With Sum
Core
1094
Car Pooling
Difference-array problems
1109
Corporate Flight Bookings
Difference-array problems
2381
Shifting Letters II
Difference-array problems
33
Search in Rotated Sorted Array
Standard binary searchPriority #11
153
Find Minimum in Rotated Sorted Array
Standard binary searchPriority #12
875
Koko Eating Bananas
Binary search on answerPriority #13
4
Median of Two Sorted Arrays
AdvancedHard set
34
Find First and Last Position of Element
Standard binary search
35
Search Insert Position
Standard binary search
74
Search a 2D Matrix
Standard binary search
81
Search in Rotated Sorted Array II
Standard binary search
162
Find Peak Element
Standard binary search
278
First Bad Version
Standard binary search
378
Kth Smallest Element in a Sorted Matrix
Advanced
410
Split Array Largest Sum
Binary search on answerHard set
540
Single Element in a Sorted Array
Advanced
704
Binary Search
Standard binary search
774
Minimize Max Distance to Gas Station
Binary search on answer
981
Time Based Key-Value Store
AdvancedAlso: Data Structure Design
1011
Capacity to Ship Packages Within D Days
Binary search on answer
1482
Minimum Number of Days to Make m Bouquets
Binary search on answer
2064
Minimized Maximum of Products Distributed to Any Store
Binary search on answer
20
Valid Parentheses
CorePriority #14
71
Simplify Path
Core
150
Evaluate Reverse Polish Notation
Core
155
Min Stack
CoreAlso: Data Structure Design
224
Basic Calculator
CoreHard set
227
Basic Calculator II
Core
394
Decode String
Core
402
Remove K Digits
Core
636
Exclusive Time of Functions
Core
735
Asteroid Collision
Core
921
Minimum Add to Make Parentheses Valid
Core
1249
Minimum Remove to Make Valid Parentheses
Core
739
Daily Temperatures
CorePriority #15
84
Largest Rectangle in Histogram
CorePriority #16Hard set
85
Maximal Rectangle
Advanced
316
Remove Duplicate Letters
Core
456
132 Pattern
Core
496
Next Greater Element I
Core
503
Next Greater Element II
Core
853
Car Fleet
Core
901
Online Stock Span
Core
907
Sum of Subarray Minimums
Core
56
Merge Intervals
CorePriority #17
57
Insert Interval
CorePriority #18
435
Non-overlapping Intervals
CorePriority #19Also: Greedy Algorithms
253
Meeting Rooms II
VariationPriority #20
228
Summary Ranges
Core
252
Meeting Rooms
Variation
352
Data Stream as Disjoint Intervals
Variation
452
Minimum Number of Arrows to Burst Balloons
CoreAlso: Greedy Algorithms
729
My Calendar I
Core
759
Employee Free Time
Variation
986
Interval List Intersections
Core
1235
Maximum Profit in Job Scheduling
VariationHard set
2406
Divide Intervals Into Minimum Number of Groups
Core
206
Reverse Linked List
CorePriority #21
141
Linked List Cycle
CorePriority #22
143
Reorder List
CorePriority #23
138
Copy List with Random Pointer
CorePriority #24
146
LRU Cache
VariationPriority #25Also: Data Structure Design
2
Add Two Numbers
Core
19
Remove Nth Node From End
Core
21
Merge Two Sorted Lists
Core
23
Merge k Sorted Lists
VariationHard setAlso: Heap and Priority Queue
25
Reverse Nodes in k-Group
VariationHard set
92
Reverse Linked List II
Variation
142
Linked List Cycle II
Core
148
Sort List
Variation
234
Palindrome Linked List
Core
708
Insert into a Sorted Circular Linked List
Variation
876
Middle of the Linked List
Core
104
Maximum Depth of Binary Tree
FoundationPriority #26
543
Diameter of Binary Tree
FoundationPriority #27
102
Binary Tree Level Order Traversal
FoundationPriority #28
98
Validate Binary Search Tree
BST problemsPriority #29
236
Lowest Common Ancestor of a Binary Tree
Tree construction and pathsPriority #30
105
Construct Binary Tree from Preorder and Inorder
Tree construction and pathsPriority #31
124
Binary Tree Maximum Path Sum
AdvancedPriority #32Hard set
297
Serialize and Deserialize Binary Tree
AdvancedPriority #33Hard set
100
Same Tree
Foundation
101
Symmetric Tree
Foundation
103
Binary Tree Zigzag Level Order Traversal
Foundation
110
Balanced Binary Tree
Foundation
112
Path Sum
Tree construction and paths
113
Path Sum II
Tree construction and paths
114
Flatten Binary Tree to Linked List
Tree construction and paths
129
Sum Root to Leaf Numbers
Tree construction and paths
173
Binary Search Tree Iterator
BST problems
199
Binary Tree Right Side View
Foundation
226
Invert Binary Tree
Foundation
230
Kth Smallest Element in a BST
BST problems
235
Lowest Common Ancestor of a BST
BST problems
314
Binary Tree Vertical Order Traversal
Advanced
337
House Robber III
Advanced
426
Convert BST to Sorted Doubly Linked List
BST problems
437
Path Sum III
Tree construction and paths
450
Delete Node in a BST
BST problems
572
Subtree of Another Tree
Foundation
662
Maximum Width of Binary Tree
Advanced
863
All Nodes Distance K in Binary Tree
Advanced
938
Range Sum of BST
BST problems
987
Vertical Order Traversal
Advanced
1448
Count Good Nodes in Binary Tree
Tree construction and paths
215
Kth Largest Element in an Array
CorePriority #34
295
Find Median from Data Stream
CorePriority #35Hard setAlso: Data Structure Design
373
Find K Pairs with Smallest Sums
Core
502
IPO
Advanced
621
Task Scheduler
CoreAlso: Greedy Algorithms
692
Top K Frequent Words
Advanced
703
Kth Largest Element in a Stream
Core
767
Reorganize String
Core
786
K-th Smallest Prime Fraction
Advanced
857
Minimum Cost to Hire K Workers
Advanced
973
K Closest Points to Origin
Core
1046
Last Stone Weight
Core
1834
Single-Threaded CPU
Advanced
78
Subsets
CorePriority #36Also: Bit Manipulation
39
Combination Sum
CorePriority #37
46
Permutations
CorePriority #38
79
Word Search
CorePriority #39
17
Letter Combinations of a Phone Number
Core
22
Generate Parentheses
Core
37
Sudoku Solver
AdvancedHard set
40
Combination Sum II
Core
47
Permutations II
Core
51
N-Queens
AdvancedHard set
90
Subsets II
Core
93
Restore IP Addresses
Core
131
Palindrome Partitioning
Core
216
Combination Sum III
Core
282
Expression Add Operators
Advanced
301
Remove Invalid Parentheses
AdvancedHard set
473
Matchsticks to Square
Advanced
698
Partition to K Equal Sum Subsets
Advanced
200
Number of Islands
GridPriority #40
133
Clone Graph
General graph problemsPriority #41
994
Rotting Oranges
GridPriority #42
127
Word Ladder
General graph problemsHard set
130
Surrounded Regions
Grid
286
Walls and Gates
Grid
339
Nested List Weight Sum
General graph problems
399
Evaluate Division
General graph problems
417
Pacific Atlantic Water Flow
Grid
542
01 Matrix
Grid
547
Number of Provinces
General graph problemsAlso: Union-Find / Disjoint Set Union
695
Max Area of Island
Grid
752
Open the Lock
General graph problems
785
Is Graph Bipartite?
General graph problems
802
Find Eventual Safe States
General graph problemsAlso: Topological Sort
827
Making a Large Island
GridHard set
909
Snakes and Ladders
General graph problems
1091
Shortest Path in Binary Matrix
Grid
1197
Minimum Knight Moves
General graph problems
207
Course Schedule
CorePriority #43
210
Course Schedule II
Core
269
Alien Dictionary
AdvancedHard set
310
Minimum Height Trees
Core
329
Longest Increasing Path in a Matrix
AdvancedHard setAlso: Two-Dimensional Dynamic Programming
1203
Sort Items by Groups Respecting Dependencies
Core
2050
Parallel Courses III
Advanced
2115
Find All Possible Recipes from Given Supplies
Advanced
684
Redundant Connection
CorePriority #44
305
Number of Islands II
Advanced
721
Accounts Merge
Core
947
Most Stones Removed with Same Row or Column
Core
952
Largest Component Size by Common Factor
Advanced
990
Satisfiability of Equality Equations
Core
1319
Number of Operations to Make Network Connected
Core
1579
Remove Max Number of Edges to Keep Graph Fully Traversable
Advanced
743
Network Delay Time
Shortest pathPriority #45
332
Reconstruct Itinerary
Advanced
505
The Maze II
Shortest path
778
Swim in Rising Water
Shortest path
787
Cheapest Flights Within K Stops
Shortest path
815
Bus Routes
Advanced
1135
Connecting Cities With Minimum Cost
Minimum spanning tree
1192
Critical Connections in a Network
Advanced
1514
Path with Maximum Probability
Shortest path
1584
Min Cost to Connect All Points
Minimum spanning tree
1631
Path With Minimum Effort
Shortest path
1976
Number of Ways to Arrive at Destination
Shortest path
45
Jump Game II
Core
53
Maximum Subarray
Core
55
Jump Game
Core
134
Gas Station
Core
135
Candy
Core
406
Queue Reconstruction by Height
Core
678
Valid Parenthesis String
Core
763
Partition Labels
Core
846
Hand of Straights
Core
860
Lemonade Change
Core
1029
Two City Scheduling
Greedy interval problems
1899
Merge Triplets to Form Target Triplet
Core
198
House Robber
FoundationPriority #46
322
Coin Change
KnapsackPriority #47
300
Longest Increasing Subsequence
String & sequencePriority #48
5
Longest Palindromic Substring
String & sequence
32
Longest Valid Parentheses
Other important problemsHard set
70
Climbing Stairs
Foundation
91
Decode Ways
String & sequence
139
Word Break
String & sequence
140
Word Break II
Other important problems
152
Maximum Product Subarray
Other important problems
213
House Robber II
Foundation
279
Perfect Squares
Foundation
309
Best Time to Buy and Sell Stock with Cooldown
Other important problemsAlso: Stock and State-Machine DP
377
Combination Sum IV
Knapsack
416
Partition Equal Subset Sum
Knapsack
494
Target Sum
Knapsack
518
Coin Change II
Knapsack
647
Palindromic Substrings
String & sequence
740
Delete and Earn
Foundation
746
Min Cost Climbing Stairs
Foundation
1143
Longest Common Subsequence
String & sequencePriority #49
72
Edit Distance
String & sequencePriority #50Hard set
10
Regular Expression Matching
String & sequenceHard set
44
Wildcard Matching
String & sequence
62
Unique Paths
Grid
63
Unique Paths II
Grid
64
Minimum Path Sum
Grid
97
Interleaving String
String & sequence
115
Distinct Subsequences
String & sequence
120
Triangle
Grid
174
Dungeon Game
Grid
221
Maximal Square
Grid
312
Burst Balloons
AdvancedHard set
486
Predict the Winner
Advanced
516
Longest Palindromic Subsequence
String & sequence
877
Stone Game
Advanced
1039
Minimum Score Triangulation of Polygon
Advanced
1547
Minimum Cost to Cut a Stick
Advanced
122
Best Time to Buy and Sell Stock II
Core
123
Best Time to Buy and Sell Stock III
Core
188
Best Time to Buy and Sell Stock IV
Core
714
...with Transaction Fee
Core
8
String to Integer (atoi)
String & sequence
28
Find the Index of the First Occurrence in a String
String & sequence
65
Valid Number
String & sequence
187
Repeated DNA Sequences
String & sequence
208
Implement Trie
Trie problems
211
Design Add and Search Words Data Structure
Trie problems
212
Word Search II
Trie problemsHard set
421
Maximum XOR of Two Numbers in an Array
Trie problemsAlso: Bit Manipulation
459
Repeated Substring Pattern
String & sequence
648
Replace Words
Trie problems
677
Map Sum Pairs
Trie problems
1044
Longest Duplicate Substring
String & sequence
1268
Search Suggestions System
Trie problems
1392
Longest Happy Prefix
String & sequence
50
Pow(x, n)
Core
89
Gray Code
Core
136
Single Number
Core
137
Single Number II
Advanced
190
Reverse Bits
Core
191
Number of 1 Bits
Core
201
Bitwise AND of Numbers Range
Core
260
Single Number III
Core
268
Missing Number
Core
338
Counting Bits
Core
371
Sum of Two Integers
Core
1239
Maximum Length of Concatenated String with Unique Characters
Advanced
6
Zigzag Conversion
Core
48
Rotate Image
Core
54
Spiral Matrix
Core
59
Spiral Matrix II
Core
73
Set Matrix Zeroes
Core
289
Game of Life
Core
498
Diagonal Traverse
Core
874
Walking Robot Simulation
Core
885
Spiral Matrix III
Core
348
Design Tic-Tac-Toe
Core
355
Design Twitter
Core
362
Design Hit Counter
Core
432
All O(1) Data Structure
Advanced
460
LFU Cache
AdvancedHard set
622
Design Circular Queue
Core
641
Design Circular Deque
Core
716
Max Stack
Advanced
895
Maximum Frequency Stack
Advanced
1146
Snapshot Array
Core
1172
Dinner Plate Stacks
Advanced
218
The Skyline Problem
Fenwick tree and segment treeHard set
307
Range Sum Query – Mutable
Fenwick tree and segment tree
315
Count of Smaller Numbers After Self
Fenwick tree and segment tree
327
Count of Range Sum
Fenwick tree and segment tree
493
Reverse Pairs
Fenwick tree and segment tree
699
Falling Squares
Fenwick tree and segment tree
715
Range Module
Fenwick tree and segment tree
1649
Create Sorted Array through Instructions
Fenwick tree and segment tree
43
Multiply Strings
Core
68
Text Justification
CoreHard set
166
Fraction to Recurring Decimal
Core
204
Count Primes
Core
273
Integer to English Words
CoreHard set
382
Linked List Random Node
Core
384
Shuffle an Array
Core
398
Random Pick Index
Core
470
Implement Rand10() Using Rand7()
Core
528
Random Pick with Weight
Core