DSA Patterns

20 patterns · ordered easy → hard · click a row to practice

Two Pointers

(2)

#	Pattern	Description	Difficulty
1	Two Pointers	Technique using two indices to traverse arrays or strings efficiently, often for pair problems and in-place operations.	easy	View
2	Fast and Slow Pointers	Uses two pointers moving at different speeds to detect cycles or find middle elements.	easy	View

Sliding Window

(1)

#	Pattern	Description	Difficulty
1	Sliding Window	Optimized approach to process subarrays or substrings by maintaining a dynamic window.	easy	View

Hashing

(1)

#	Pattern	Description	Difficulty
1	HashMap and HashSet	Data structures providing constant time complexity for insertions and lookups.	easy	View

Mathematics

(1)

#	Pattern	Description	Difficulty
1	Math	Mathematical techniques including number theory, combinatorics, and modular arithmetic.	easy	View

Binary Search Trees

(1)

#	Pattern	Description	Difficulty
1	Binary Search	Efficient searching algorithm that divides the search space in half on sorted data.	easy	View

Trees

(2)

#	Pattern	Description	Difficulty
1	Tree Traversals	Techniques for visiting nodes in trees such as inorder, preorder, and postorder.	easy	View
2	Trie	Tree-like structure used for efficient prefix-based searching and string operations.	medium	View

Searching

(1)

#	Pattern	Description	Difficulty
1	Depth First Search	Traversal technique exploring as far as possible along each branch before backtracking.	medium	View

Queues

(2)

#	Pattern	Description	Difficulty
1	Breadth First Search	Traversal technique exploring nodes level by level using a queue.	medium	View
2	Heap and Priority Queue	Data structure used for efficiently retrieving minimum or maximum elements.	medium	View

Greedy Algorithms

(1)

#	Pattern	Description	Difficulty
1	Greedy	Algorithmic approach making locally optimal choices to achieve a global optimum.	medium	View

Stacks

(2)

#	Pattern	Description	Difficulty
1	Backtracking	Recursive approach to explore all possible solutions and backtrack when needed.	medium	View
2	Monotonic Stack	Stack-based technique maintaining increasing or decreasing order for efficient queries.	medium	View

Divide and Conquer

(1)

#	Pattern	Description	Difficulty
1	Divide and Conquer	Approach that divides a problem into smaller subproblems and combines their results.	medium	View

Topological Sort

(1)

#	Pattern	Description	Difficulty
1	Topological Sort	Linear ordering of nodes in a directed acyclic graph based on dependencies.	medium	View

Union Find

(1)

#	Pattern	Description	Difficulty
1	Union Find	Disjoint set data structure used for tracking connected components.	medium	View

Shortest Path

(1)

#	Pattern	Description	Difficulty
1	Shortest Path	Algorithms to find the shortest path between nodes in weighted graphs.	hard	View

Dynamic Programming

(1)

#	Pattern	Description	Difficulty
1	Dynamic Programming	Optimization technique solving problems with overlapping subproblems using memoization or tabulation.	hard	View

Bit Manipulation

(1)

#	Pattern	Description	Difficulty
1	Bit Manipulation	Techniques using binary representations for efficient computations.	medium	View