README.md

JAVA DATA STRUCTURES & ALGORITHMS

• Normalprgms

Liner

• Array
• LinkedList
• String

Sorting

• Sorting

Trees

• Trees

Blind 75

18/75 Completed

• Array (10)
• Binary (5)
• Dynamic Programming (11)
• Graph (8)
• Interval (5)
• Linked-List (6)
• Matrix (4)
• String (10)
• Tree (14)
• Heap (3)

Tips to Consider

If input array is sorted then
    - Binary search
    - Two pointers

If asked for all permutations/subsets then
    - Backtracking

If given a tree then
    - DFS
    - BFS

If given a graph then
    - DFS
    - BFS

If given a linked list then
    - Two pointers

If recursion is banned then
    - Stack

If must solve in-place then
    - Swap corresponding values
    - Store one or more different values in the same pointer

If asked for maximum/minumum subarray/subset/options then
    - Dynamic programming

If asked for top/least K items then
    - Heap

If asked for common strings then
    - Map
    - Trie

Else
    - Map/Set for O(1) time & O(n) space
    - Sort input for O(nlogn) time and O(1) space

It is highly recommended to read chapters 1, 2, 3, 4, 8, and 10 of [Cracking The Coding Interview] to familiarize yourself with the following data structures and their operations:

• Arrays
• Maps
• Linked Lists
• Queues
• Heaps
• Stacks
• Trees
• Graphs

In addition, you should have a good grasp on common algorithms such as:

• Breadth-first search
• Depth-first search
• Binary search
• Recursion

Important Links:

-Important-and-Useful-links-from-all-over-the-LeetCode

• 14 Patterns to Ace Any Coding Interview Question
• Grokking the Coding Interview: Patterns for Coding Questions
• Cracking the Coding Interview PDF
• Sean Prashad's Leetcode Patterns
• Top Interview Questions - Leetcode Medium Collection
• Technical Interview Handbook - Interview Prep Materials for Busy Engineers
• Comprehensive Data Structure and Algorithm Study Guide

Array

• Two Sum
• Best Time to Buy and Sell Stock
• Contains Duplicate
• Product of Array Except Self
• Maximum Subarray
• Maximum Product Subarray
• Find Minimum in Rotated Sorted Array
• Search in Rotated Sorted Array
• 3Sum
• Container With Most Water

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Binary

• Sum of Two Integers
• Number of 1 Bits
• Counting Bits
• Missing Number
• Reverse Bits

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Dynamic Programming

• Climbing Stairs
• Coin Change
• Longest Increasing Subsequence
• Longest Common Subsequence
• Word Break Problem
• Combination Sum
• House Robber
• House Robber II
• Decode Ways
• Unique Paths
• Jump Game

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Graph

• Clone Graph
• Course Schedule
• Pacific Atlantic Water Flow
• Number of Islands
• Longest Consecutive Sequence
• Alien Dictionary (Leetcode Premium)
• Graph Valid Tree (Leetcode Premium)
• Number of Connected Components in an Undirected Graph (Leetcode Premium)

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Interval

• Insert Interval
• Merge Intervals
• Non-overlapping Intervals
• Meeting Rooms (Leetcode Premium)
• Meeting Rooms II (Leetcode Premium)

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Linked List

• Reverse a Linked List
• Detect Cycle in a Linked List
• Merge Two Sorted Lists
• Merge K Sorted Lists
• Remove Nth Node From End Of List
• Reorder List

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Matrix

• Set Matrix Zeroes
• Spiral Matrix
• Rotate Image
• Word Search

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String

• Longest Substring Without Repeating Characters
• Longest Repeating Character Replacement
• Minimum Window Substring
• Valid Anagram
• Group Anagrams
• Valid Parentheses
• Valid Palindrome
• Longest Palindromic Substring
• Palindromic Substrings
• Encode and Decode Strings (Leetcode Premium)

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Tree

• Maximum Depth of Binary Tree
• Same Tree
• Invert/Flip Binary Tree
• Binary Tree Maximum Path Sum
• Binary Tree Level Order Traversal
• Serialize and Deserialize Binary Tree
• Subtree of Another Tree
• Construct Binary Tree from Preorder and Inorder Traversal
• Validate Binary Search Tree
• Kth Smallest Element in a BST
• Lowest Common Ancestor of BST
• Implement Trie (Prefix Tree)
• Add and Search Word
• Word Search II

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Heap

• Merge K Sorted Lists
• Top K Frequent Elements
• Find Median from Data Stream