Coding Interview Algorithms: Complete Guide

Master all essential coding interview algorithms ordered by importance for AI/ML interviews. Detailed explanations, step-by-step implementations, and real-world examples with comprehensive code walkthroughs.

Chapter 1: Arrays & Strings

Two Pointers, Sliding Window, Hash Maps

  • Two pointers technique
  • Sliding window patterns
  • Hash maps and sets
  • String manipulation
  • Prefix sums and Kadane's algorithm
Arrays Strings Two Pointers

Chapter 2: Trees & Binary Trees

DFS, BFS, BST, Tree Construction

  • Tree traversals (DFS, BFS)
  • Binary Search Trees
  • Tree construction problems
  • Lowest Common Ancestor
  • Tree validation
Trees BST Traversal

Chapter 3: Dynamic Programming

1D/2D DP, Memoization, Classic Patterns

  • 1D and 2D DP problems
  • Memoization techniques
  • Knapsack problems
  • Longest Common Subsequence
  • State transitions
DP Memoization Optimization

Chapter 4: Graphs

DFS, BFS, Shortest Paths, Topological Sort

  • Graph representation
  • DFS and BFS traversal
  • Shortest path algorithms
  • Topological sorting
  • Union-Find (Disjoint Set)
Graphs DFS BFS

Chapter 5: Binary Search

Search in Sorted Arrays, Search Space Reduction

  • Classic binary search
  • Search in rotated arrays
  • Search space reduction
  • Finding boundaries
  • Binary search on answer
Binary Search Search Optimization

Chapter 6: Stacks & Queues

Monotonic Stacks, Priority Queues, BFS

  • Stack operations and applications
  • Monotonic stacks
  • Priority queues and heaps
  • BFS with queues
  • Expression evaluation
Stacks Queues Heaps

Chapter 7: Backtracking

Permutations, Combinations, Constraint Satisfaction

  • Backtracking fundamentals
  • Permutations and combinations
  • Constraint satisfaction
  • Pruning strategies
  • N-Queens and Sudoku
Backtracking Recursion Pruning

Chapter 8: Greedy Algorithms

Activity Selection, Interval Scheduling

  • Greedy choice property
  • Activity selection problem
  • Interval scheduling
  • Huffman coding
  • When to use greedy
Greedy Optimization Intervals

Chapter 9: Linked Lists

Traversal, Reversal, Fast/Slow Pointers

  • Linked list traversal
  • Reversing linked lists
  • Fast and slow pointers
  • Merging and intersection
  • Cycle detection
Linked Lists Pointers Cycles

Chapter 10: Bit Manipulation

Bitwise Operations, Common Tricks, XOR Patterns

  • Bitwise operations (AND, OR, XOR)
  • Bit manipulation tricks
  • XOR patterns
  • Counting bits
  • Power of two checks
Bit Manipulation XOR Optimization