DSA Tracker

Your DSA Journey

Practice 425 curated DSA problems by pattern. Browse freely, then sign in to save progress, notes, and revision history.

Track 425+ curated problems with spaced repetition

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DSA Prep — Problems
#
Problem
Difficulty
Actions
Bitwise XOR - Finding Single/Missing Number
Bitwise AND - Counting Set Bits (Hamming Weight)
Bitwise DP - Counting Bits Optimization
Bitwise Operations - Arithmetic Without +/-
Bitwise Operations - Power of Two/Four Check
Two Pointers - Converging (Sorted Array Target Sum)
15
Medium
16
Medium
17
Medium
22
Medium
Two Pointers - Fast & Slow (Cycle Detection)
Two Pointers - Fixed Separation (Nth Node from End)
Two Pointers - In-place Array Modification
32
Medium
Two Pointers - String Comparison with Backspaces
Two Pointers - Expanding From Center (Palindromes)
Two Pointers - String Reversal
Sliding Window - Fixed Size (Subarray Calculation)
Sliding Window - Variable Size (Condition-Based)
Sliding Window - Monotonic Queue for Max/Min
75
Medium
Sliding Window - Character Frequency Matching
76
Easy
Tree BFS - Level Order Traversal
Tree DFS - Recursive Preorder Traversal
84
Easy
Tree DFS - Recursive Inorder Traversal
Tree - Lowest Common Ancestor (LCA) Finding
Tree - Serialization and Deserialization
Graph DFS - Connected Components / Island Counting
117
Easy
Graph BFS - Connected Components / Island Counting
123
Medium
Graph DFS - Cycle Detection (Directed Graph)
Graph BFS - Topological Sort (Kahn's Algorithm)
Graph - Deep Copy / Cloning
139
Medium
Graph - Shortest Path (Bellman-Ford / BFS+K)
Strongly Connected Components (Kosaraju / Tarjan)
Bridges & Articulation Points (Tarjan low-link)
Minimum Spanning Tree (Kruskal / Prim / DSU + heap)
Bidirectional BFS (BFS optimization for known source & target)
179
Hard
DP - 1D Array (Fibonacci Style)
181
Medium
182
Medium
DP - 1D Array (Kadane's Algorithm for Max/Min Subarray)
DP - 1D Array (Coin Change / Unbounded Knapsack Style)
193
Medium
DP - 1D Array (0/1 Knapsack Subset Sum Style)
197
Medium
DP - 1D Array (Word Break Style)
198
Medium
DP - 2D Array (Longest Common Subsequence - LCS)
DP - 2D Array (Edit Distance / Levenshtein Distance)
203
Medium
DP - 2D Array (Unique Paths on Grid)
206
Medium
209
Medium
DP - Interval DP
DP - Catalan Numbers
DP - Longest Increasing Subsequence (LIS)
Heap - Top K Elements (Selection/Frequency)
Heap - Two Heaps for Median Finding
Heap - K-way Merge
Heap - Scheduling / Minimum Cost (Greedy with Priority Queue)
Backtracking - Subsets (Include/Exclude)
250
Medium
251
Medium
252
Medium
Backtracking - Permutations
254
Medium
Backtracking - Combination Sum
Backtracking - Parentheses Generation
Backtracking - Word Search / Path Finding in Grid
260
Medium
Backtracking - N-Queens / Constraint Satisfaction
263
Hard
Backtracking - Palindrome Partitioning
Greedy - Interval Merging/Scheduling
Greedy - Jump Game Reachability/Minimization
270
Medium
271
Medium
Greedy - Buy/Sell Stock
Greedy - Gas Station Circuit
274
Medium
Greedy - Task Scheduling (Frequency Based)
Greedy - Sorting Based
277
Hard
Binary Search - On Sorted Array/List
281
Easy
Binary Search - Find Min/Max in Rotated Sorted Array
Binary Search - Find First/Last Occurrence
Binary Search - Median / Kth across Two Sorted Arrays
Stack - Valid Parentheses Matching
Stack - Monotonic Stack
Stack - Expression Evaluation (RPN/Infix)
Stack - Simulation / Backtracking Helper
325
Medium
326
Medium
Stack - Min Stack Design
328
Medium
Stack - Largest Rectangle in Histogram
Linked List - In-place Reversal
Linked List - Merging Two Sorted Lists
Linked List - Addition of Numbers
Linked List - Intersection Detection
Linked List - Reordering / Partitioning
344
Medium
346
Medium
Array/Matrix - In-place Rotation
348
Medium
349
Medium
Array/Matrix - Spiral Traversal
351
Medium
Array/Matrix - Set Matrix Zeroes (In-place Marking)
356
Medium
Array - Product Except Self (Prefix/Suffix Products)
Array - Plus One (Handling Carry)
361
Easy
364
Easy
Array - Merge Sorted Array (In-place from End)
Array - Cyclic Sort
String - Palindrome Check (Two Pointers / Reverse)
String - Anagram Check (Frequency Count/Sort)
String - Roman to Integer Conversion
String - String to Integer (atoi)
String - Multiply Strings (Manual Simulation)
String Matching - Naive / KMP / Rabin-Karp
String - Repeated Substring Pattern Detection
Design (General/Specific)
386
Medium
387
Medium
401
Hard
408
Medium
Tries
422
Medium
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Problems are grouped by recurring interview patterns, helping learners practice concepts instead of random lists.

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