Table of Contents

• Section 0: Patterns
• Section 1: Algorithms
• Section 2: Data Structures
• Section 3: Time & Space Complexities
• Section 4: Auxiliary Collection of Problems & Solutions

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Section 0: Patterns

• Ref 1: LeetCode Patterns
• Ref 2: 14 Patterns

Condition	Algorithms to / can Use	Data Structures to / can Use
Input array is sorted	Binary Search + Two Pointers	--
Asking for all permutations / subsets / combinations	DFS Backtracking	--
Finding the minimum / maximum / k-th position	Binary Search + Heap	--
Binary tree / binary search tree	BFS using queues + DFS using recursion	BT + BST
Path finding on a grid / matrix	BFS using queues + DFS using recursion + Step towards directions	--
Linked list	Two Pointers + Dummy Node	Linked List
K-Sum / partitioning	Two Pointers	--
Substring / subarray on linear structure	Sliding Window (Two Pointers)	--
Dealing with brackets	--	Stack
Finding occurrence of a certain pattern	--	Hash Table (Dict, Counter)
Maximum / minimum subarray / subset / options	Dynamic Programming	--

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Section 1: Algorithms

ID	Algorithm	When To Use	Study Guide	Problems	Solutions	Important Key Points
1	Binary Search	"minimizing / maximizing / find K-th position"	Guide	Problems	Solutions	✅ A Template
2	Greatest Common Divisor (GCD) & Least Common Multiple (LCM)	"total number of positive integers <= N which are divisible by a or b or c"	Guide	-	-	✅ Calculation Formulae in Python
3	DFS Recursion & Backtracking	"combination / combination sum / permutations / subsets"	Guide	Problems	Solutions	✅ A Template
4	Two Pointers	"K-Sum / partitioning / sorting"	Guide	Problems	Solutions	-
5	Topological DFS & BFS	"path finding in a grid or matrix"	-	Problems	Solutions
6	Sorting Methods	-	Guide	Problems	Solutions
7	Dynamic Programming	-	Merged with Problems	Problems	Solutions
8	Prefix & Sufix Sum

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Section 2: Data Structures

ID	Data Structure	Common Topics / Applications	Study Guide	Problems	Solutions	Important Key Points
1	Binary Tree & Binary Search Trees	"BT and BST traversal / deleting & inserting node / root-to-leaf DFS / construction / validation"	Guide	Problems	Solutions	✅ Traversal Templates
2	Hash Table	"using Counter / Set / Dictionary / Pattern Hashing"	Guide	Problems	Solutions	✅ Using and Sorting Python Dictionary & Counter
3	Linked List	"Linked List cycle detection / cycle locating / slow-fast pointers / dummy nodes / double pointers"	Guide	Problems	Solutions	-
4	Binary Indexed Tree / Fenwick Tree
5	Heaps
6	Trie / Prefix Tree

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Section 3: Time & Space Complexities

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Section 4: Auxiliary Problems & Solutions

4.1 LeetCode Top 100 - [Problems] | [Solutions]

4.2 LintCode Top 100 - [Problems] | [Solutions]

4.3 LintCode Chapter-by-Chapter Practice - [Problems] | [Solutions]