- Convert Sorted Array to Binary Search Tree
- Binary Tree Inorder Traversal
- Count Pairs With Given Sum
- Wifi Range
- Merge Strings Alternately
- Kids With the Greatest Number of Candies
- Antique Collections
- Valid Palindrome
- Length of Last Word
- Dominant Pairs
- Removing Stars From a String
- Maximum Length
- Accept the challenge
- Find the Longest Balanced Substring of a Binary String
- Make the Array Beautiful
- Add minimum characters
- Equal Left and Right Subarray Sum
- Count Special Numbers
- Optimal Partition of String
- Minimum Steps Required
- Remainder on dividing by 11
- Maximize sum
- Successful Pairs of Spells and Potions
- Array Subset of another array
- Array Pair Sum Divisibility Problem
- Make Array Elements Equal
- Number of Even and Odd Bits
- Minimum Integer
- Reducing Dishes
- K Items With the Maximum Sum
- Count the substrings
- Shy Geek
- Minimum Cost For Tickets
- Valuable String
- Frogs and Jumps
- Taxi Booking
- Shortest XY distance in Grid
- Distinct Difference
- Design Browser History
- Number of Subarrays of 0's
- Count the Number of Vowel Strings in Range
- Check Completeness of a Binary Tree
- Count distinct elements in every window
- Symmetric Tree
- Maximum Possible Value
- Make array beautiful
- Calculate the work done
- Binary matrix having maximum number of 1s
- Yet another query problem
- Convert Sorted List to Binary Search Tree
- Maximum Triplet product
- Linked List Cycle II
- Find anagrams in linked list
- Sort the Students by Their Kth Score
- Minimum Time to Complete Trips
- Max Level Sum in Binary Tree
- Longest Common Substring
- Kth Missing Positive Number
- Geek hates too many 1s
- Save Flowers
- Nice Array
- Avoid Fire
- Alternating Digit Sum
- Kth smallest element
- Find Missing And Repeating
- Count Subarrays With Fixed Bounds
- Common elements
- Best Node
- Number of Valid Words in a Sentence
- Cutting Rectangles
- Walls Coloring II
- Update Queries
- Sort an Array
- Intersection of Multiple Arrays
- Count Lattice Points Inside a Circle
- Optimal Array
- Find Duplicate Subtrees
- Reverse both parts
- Maximize the Topmost Element After K Moves
- Get minimum element from stack
- Find All K-Distant Indices in an Array
- Count Artifacts That Can Be Extracted
- Construct Quad Tree
- Number of Good Components
- Left and Right Sum Differences
- Find the Maximum Number of Marked Indices
- Find the Divisibility Array of a String
- Valid Compressed String
- Shortest Impossible Sequence of Rolls
- Number of Zero-Filled Subarrays
- Implement Atoi
- Design a Number Container System
- Best Poker Hand
- Find Subarrays With Equal Sum
- Unique Paths in a Grid
- IPO
- Increment Submatrices by One
- Difference Between Element Sum and Digit Sum of an Array
- Magical String
- Count the triplets
- Connect Nodes at Same Level
- Capacity To Ship Packages Within D Days
- Two Best Non-Overlapping Events
- Reverse a String
- Multiply two strings
- Fill the Matrix
- Minimum Operations to Reduce an Integer to 0
- Merge Two 2D Arrays by Summing Values
- Find Transition Point
- Count Cyclic Paths
- Minimum Score by Changing Two Elements
- Maximum Difference by Remapping a Digit
- Fixing Two Swapped nodes of a BST
- Finding middle element in a linked list
- Binary Tree Zigzag Level Order Traversal
- Partition String Into Substrings With Values at Most K
- Distinct Prime Factors of Product of Array
- Count the Digits That Divide a Number
- Binary Search
- Apple Sequences
- Minimum Distance Between BST Nodes
- Minimum Common Value
- Minimum Absolute Difference in BST
- Is it Fibonacci
- Find duplicates in an array
- Separate the Digits in an Array
- Maximum Number of Integers to Choose From a Range I
- Good Stones
- Geeks Island
- Add to Array-Form of Integer
- Walls Coloring
- Find the Array Concatenation Value
- Count the Number of Fair Pairs
- Count Odd Numbers in an Interval Range
- Arithmetic Number
- Prime List
- Minimum Fuel Cost to Report to the Capital
- Min Jump
- Shortest Path with Alternating Colors
- Minimum Days
- Balloon Everywhere
- As Far from Land as Possible
- Naming a Company
- Maximum Bipartite Matching
- Count number of free cell
- Length of the longest subarray with positive product
- Fruit Into Baskets
- Shuffle the Array
- BST Downward Traversal
- Range OR
- Mex Array
- Equal grouping
- Max Sum without Adjacents
- Last cell in a Matrix
- Verifying an Alien Dictionary
- Largest Sum Cycle
- Greatest Common Divisor of Strings
- Distinct Coloring
- Minimum times A has to be repeated such that B is a substring of it
- Best Team With No Conflicts
- Sort Integers by The Power Value
- Select Nodes
- N-th Tribonacci Number
- Min operations
- LFU Cache
- All Numbers
- Scrambled String
- Data Stream as Disjoint Intervals
- Total Decoding Messages
- Concatenated Words
- Cheapest Flights Within K Stops
- Type it!
- Find Closest Node to Given Two Nodes
- Xenny and Coin Rank
- Snakes and Ladders
- LCM hates GCD
- Convert an array to reduced form
- Tax in Chefland
- Split The String
- Reach on Time
- Next Greater Element
- Minimum Operations
- Fitness
- Geeks And The String
- Game Points
- Fitness
- Determine the Score
- Chef Plays Ludo
- Burgers
- Audible Range
- Palindrome Partitioning
- GCD Array
- Restore IP Addresses
- Minimum X (xor) A
- Non-decreasing Subsequences
- Maximum Weight Node
- Subarray Sums Divisible by K
- Carpet into Box
- Using a Robot to Print the Lexicographically Smallest String
- Remove Outermost Parentheses
- Maximum Sum Circular Subarray
- Find the first node of loop in linked list
- Apply Discount to Prices
- Subtract the Product and Sum of Digits of an Integer
- Populating Next Right Pointers in Each Node II
- Longest Subarray With Maximum Bitwise AND
- Last Stone Weight
- Invalid Transactions
- Flip String to Monotone Increasing
- Find the maximum GCD of the siblings of a Binary Tree
- The Number of Weak Characters in the Game
- Find Bottom Left Tree Value
- Ugly Number
- Largest Local Values in a Matrix
- Find the Index of the First Occurrence in a String
- Decode the Slanted Ciphertext
- Average Waiting Time
- Rotate Image
- Reordered Power of 2
- Merging Details
- Decode Ways
- Power of Three
- Palindrome Linked List
- Maximum Number of Points with Cost
- Power of Four
- Stamping The Sequence
- Sum of two large numbers
- Running Sum of 1d Array
- Find Pivot Index
- Min Cost Climbing Stairs
- Longest Palindromic Substring
- Split Array into Consecutive Subsequences
- Valid Anagram
- Reduce Array Size to The Half
- Ransom Note
- Longest Sub-Array with Sum K
- First Unique Character in a String
- Valid Sudoku
- Unique Morse Code Words
- Reshape the Matrix
- Knight Walk
- Number of Turns in Binary Tree
- Intersection of Two Arrays II
- Substring with Concatenation of All Words
- Max length chain
- Contains Duplicate
- Unique BST's
- Sum of all substrings of a number
- Stickler Thief
- Shortest Common Supersequence
- Partition Equal Subset Sum
- Optimal Strategy For A Game
- Number of Unique Paths
- Maximize The Cut Segments
- Max sum subarray by removing at most one element
- Longest Increasing Subsequence
- Longest Common Subsequence
- Equal Sum Partition
- Egg Dropping Puzzle
- 0 - 1 Knapsack Problem
- Ways to write n as sum
- Reach a given score
- nCr
- Minimum number of jumps
- Kadane's Algorithm - II
- Kadane's Algorithm - I
- Count ways to reach the n'th stair
- Count ways to N'th Stair(Order does not matter)
- Count number of hops
- Coin Change - Number of ways
- Coin Change - Minimum number of coins
- Print first n Fibonacci Numbers
- Nth catalan number
- Fibonacci Numbers - Top Down DP
- Fibonacci Numbers - Bottom Up DP
- Contiguous Elements XOR
- Camel Case
- Trie | (Insert and Search)
- Search Query for Strings
- Renaming Cities
- Most frequent word in an array of strings
- Unique Subsets
- Union-Find
- Solve the Sudoku
- Number of Connected Components
- Minimum Spanning Tree using Kruskal
- M-Coloring Problem
- Detect Cycle using DSU
- Combination Sum
- Black and White
- Rat Maze With Multiple Jumps
- N meetings in one room
- Largest number with given sum
- Largest number in K swaps
- Job Sequencing Problem
- Huffman Decoding
- Fractional Knapsack
- Activity Selection
- X Total Shapes
- Unit Area of largest region of 1's
- Strongly Connected Components (Kosaraju's Algo)
- Strongly connected component (Tarjans's Algo)
- Steps by Knight
- Rotten Oranges
- Possible paths between 2 vertices
- Mother Vertex
- Minimum Swaps to Sort
- Minimum Spanning Tree
- Minimum Cost Path
- Implementing Dijkstra Algorithm
- Distance of nearest cell having 1
- Bridge edge in a graph
- Articulation Point - II
- Articulation Point - I
- Topological sort
- Level of Nodes
- Find whether path exist
- Find the number of islands
- DFS of Graph
- Detect cycle in an undirected graph
- Detect cycle in an directed graph
- BFS of graph
- Print adjacency list
- Rearrange characters
- Nearly sorted
- Minimum Cost of ropes
- Merge k Sorted Arrays
- Kth smallest element
- Kth largest element
- Kth largest element in a stream
- K Most occurring elements
- K largest elements
- Heap Sort
- Find median in a stream
- Binary Heap Operations
- Stack using two queues
- Rotate Deque By K
- Reverse First K elements of Queue
- Queue using two Stacks
- Queue Reversal
- Preorder to Postorder
- Operations on Queue
- Minimum BST Sum Subtree
- Merge two BST 's
- Maximum of all subarrays of size k
- LCA of 3 nodes
- Insertion in deque
- Implement Queue using Linked List
- Implement Queue using array
- Generate Binary Numbers
- Fixing Two nodes of a BST
- Dequeue Traversal
- Deque Implementations
- Deque deletion
- Circular tour
- Vertical Traversal of Binary Tree
- Top View of Binary Tree
- Smaller on Right
- Search a node in a BST
- Print BST elements in given range
- Pair Sum in BST
- Minimum element in BST
- Lowest Common Ancestor in a BST
- Levelorder traversal of a BST
- Insert a node in a BST
- Inorder traversal of a BST
- Floor in BST
- Find Common Nodes in two BSTs
- Find the Closest Element in BST
- Delete a node from BST
- Count BST nodes that lie in a given range
- Convert Level Order Traversal to BST
- Check for BST
- Ceil in BST
- Bottom View of Binary Tree
- ZigZag Tree Traversal
- Tree from Postorder and Inorder
- Serialize and Deserialize a Binary Tree
- Node at distance
- Maximum sum of Non-adjacent nodes
- Maximum path sum from any node
- Maximum difference between node and its ancestor
- Foldable Binary Tree
- Count Number of SubTrees having given Sum
- Construct Binary Tree from Parent Array
- Connect Nodes at Same Level
- Vertical Width of a Binary Tree
- Right View of Binary Tree
- Preorder Traversal
- Postorder Traversal
- Mirror Tree
- Maximum Width of Tree
- Make Binary Tree From Linked List
- Lowest Common Ancestor in a Binary Tree
- Level order traversal
- Level order traversal Line by Line
- Level order traversal in spiral form
- Left View of Binary Tree
- Inorder Traversal
- Height of Binary Tree
- Diameter of a Binary Tree
- Determine if Two Trees are Identical
- Children Sum Parent
- Check if subtree
- Check for Balanced Tree
- Binary Tree to DLL
- Binary Tree to CDLL
- The Celebrity Problem
- Maximum Rectangular Area in a Histogram
- Maximum of minimum for every window size
- Stock span problem
- Removing consecutive duplicates
- Removing consecutive duplicates - 2
- Parenthesis Checker
- Operations on Stack
- Next Greater Element
- Infix to Postfix
- Implement Stack using Linked List
- Implement stack using array
- Implement two stacks in an array
- Get min at pop
- Evaluation of Postfix Expression
- Delete middle element of a stack
- Merge Sort on Doubly Linked List
- Merge Sort for Linked List
- Merge K sorted linked lists
- LRU Cache
- Intersection Point in Y Shapped Linked Lists
- Given a linked list of 0s, 1s and 2s, sort it.
- Clone a linked list with next and random pointer
- Add two numbers represented by linked lists
- Swap Kth nodes from ends
- Rotate a Linked List
- Reverse a linked list
- Remove loop in Linked List
- Pairwise swap of nodes in LinkedList
- Find length of Loop
- Detect Loop in linked list
- Check if Linked List is Palindrome
- Add two numbers represented by linked lists
- Remove duplicates from an unsorted linked list
- Remove duplicate element from sorted Linked List
- Nth node from end of linked list
- Merge two sorted linked lists
- Insert in Middle of Linked List
- Identical Linked Lists
- Doubly linked list Insertion at given position
- Delete without head pointer
- Linked List Insertion
- Count nodes of linked list
- Split the binary string into substrings with equal number of 0s and 1s
- Permutations of a given string
- Parenthesis Checker
- Palindrome String
- Next Permutation
- Longest Repeating Subsequence
- Longest Palindrome in a String
- Edit Distance
- Count the Reversals
- Convert a sentence into its equivalent mobile numeric keypad sequence
- The Modified String
- Sum of numbers in string
- Smallest window in a string containing all the characters of another string
- Reverse words in a given string
- Repeating Character - First Appearance Leftmost
- Remove common characters and concatenate
- Rabin Karp - Pattern Searching
- Pattern Search KMP
- Pangram Checking
- Nth number made of prime digits
- Non Repeating Character
- Minimum indexed character
- Maximum Occuring Character
- Lexicographic Rank Of A String
- Keypad typing
- Isomorphic Strings
- Implement strstr
- Check if string is rotated by two places
- Check if strings are rotations of each other or not
- Check if a String is Subsequence of Other
- Check if a string is Isogram or not
- Case-specific Sorting of Strings
- Binary String
- Anagram
- Pattern Search
- Naive Pattern Search
- Kth Largest Element in an Array
- Zero Sum Subarrays
- Winner of an election
- Subarrays with equal 1s and 0s
- Subarray with 0 sum
- Subarray range with given sum
- Sorting Elements of an Array by Frequency
- Sort an array according to the other
- Positive Negative Pair
- Numbers containing 1, 2 and 3
- Longest consecutive subsequence
- Union of two arrays
- Separate chaining in Hashing
- Quadratic Probing in Hashing
- Print Non-Repeated Elements
- Linear Probing in Hashing
- Intersection of two arrays
- Hashing for pair - 1
- First Repeating Element
- Count Non-Repeated Elements
- Check if two arrays are equal or not
- Transpose of Matrix
- Sum of upper and lower triangles
- Spirally traversing a matrix
- Sorted matrix
- Search in a row-column sorted Matrix
- Row with max 1s
- Rotate by 90 degree
- Reversing the columns of a Matrix
- Print Matrix in snake Pattern
- Multiply the matrices
- Median in a row-wise sorted Matrix
- Make Matrix Beautiful
- Kth element in Matrix
- Interchanging the rows of a Matrix
- Exchange matrix columns
- Determinant of a Matrix
- Boundary traversal of matrix
- Boolean Matrix
- Adding two matrices
- Union of Two Sorted Arrays
- Triplet Sum in Array
- Three way partitioning
- Sort by Absolute Difference
- Number of pairs
- Minimum Platforms
- Minimum Difference in an Array
- Merge Without Extra Space
- Merge three sorted arrays
- Kth smallest element
- Intersection of two sorted arrays
- Find triplets with zero sum
- Counting Sort
- Count the number of possible triangles
- Count Inversions
- Closet 0s 1s and 2s
- Closer to sort
- Quick Sort
- Insertion Sort
- Bubble Sort
- Binary Array Sorting
- Median of Two sorted arrays
- Subarray with given sum
- Count only Repeated
- Count More than n/k Occurences
- Allocate minimum number of pages
- Two Repeated Elements
- Roof Top
- Minimum Number in a sorted rotated array
- Maximum Water Between Two Buildings
- Floor in a Sorted Array
- Square root of a number
- Peak element
- Majority Element
- Left Index
- Count 1's in binary array
- Wave Array
- Trapping Rain Water
- Stock buy and sell
- Smallest Positive missing number
- Rearrange Array Alternately
- Rearrange an array with O(1) extra space
- Maximum occured integer
- Maximum Index
- Leaders in an array
- Frequencies of Limited Range Array Elements
- Equilibrium Point
- Strongest Neighbour
- Rotate Array
- Reverse array in groups
- Minimum adjacent difference in a circular array
- Mean And Median of Array
- Max Circular Subarray Sum
- Max and Second Max
- Longest Subarray Of Evens And Odds
- Kadane's Algorithm
- Check if array is sorted and rotated
- Array insert at index
- Tower Of Hanoi
- Power Of Numbers
- Possible Words From Phone Digits
- Missing number in array
- Lucky Numbers
- Josephus problem
- Maximum AND Value
- Count total set bits
- Boats to Save People
- Score of Parentheses
- Validate Stack Sequences
- Min Cost to Connect All Points
- Valid Parentheses
- Course Schedule
- Linked List Cycle
- Arithmetic Slices
- Is Subsequence
- Counting Bits
- Circle and Rectangle Overlapping
- Excel Sheet Column Number
- Majority Element
- Maximum Depth of Binary Tree
- Add Digits
- Remove Duplicates from Sorted Array II
- 4Sum II
- Maximum Product of Three Numbers
- Concatenation of Consecutive Binary Numbers
- Design Add and Search Words Data Structure
- All Elements in Two Binary Search Trees
- Detect Capital
- Sequential Digits
- Stone Game IV
- Can Place Flowers
- Insert into a Binary Search Tree
- Sum of Root To Leaf Binary Numbers
- Add Binary
- Robot Bounded In Circle
- Linked List Random Node
- Car Pooling
- Find the Town Judge
- Maximum Difference Between Node and Ancestor
- Smallest Integer Divisible by K
- K Closest Points to Origin
- Basic Calculator II
- Course Schedule II
- Reorder List
- Build an Array With Stack Operations
- Minimum Absolute Difference
- Decode String
- Maximum Repeating Substring
- Insertion Sort List
- Range Sum of BST
- Consecutive Characters
- Word Break
- Element Appearing More Than 25% In Sorted Array
- Find Target Indices After Sorting Array
- Jump Game III
- Same Tree
- Binary Tree Tilt
- Shift 2D Grid
- Convert Binary Number in a Linked List to Integer
- Minimum Number of Operations to Move All Balls to Each Box
- Minimum Cost to Move Chips to The Same Position
- House Robber III
- Stream of Characters
- Maximum Product Subarray
- Odd Even Linked List
- Minimum Difference Between Highest and Lowest of K Scores
- Maximal Rectangle
- Longest Consecutive Sequence
- Permutation Sequence
- Number Complement
- Complement of Base 10 Integer
- Lexicographically Smallest String After Applying Operations
- Uncommon Words from Two Sentences
- Number of Sub-arrays of Size K and Average Greater than or Equal to Threshold
- Bulls and Cows
- Delete Node in a BST
- Construct Binary Tree from Inorder and Postorder Traversal
- Single Element in a Sorted Array
- Total Hamming Distance
- Hamming Distance
- Find All Numbers Disappeared in an Array
- Dungeon Game
- Kth Smallest Number in Multiplication Table
- Largest Divisible Subset
- Iterator for Combination
- Airplane Seat Assignment Probability
- Missing Number
- Daily Temperatures
- Word Pattern
- Single Number II
- Isomorphic Strings
- Find the Difference
- String Compression
- Minimum Value to Get Positive Step by Step Sum
- Merge Intervals
- Count and Say
- Maximum Subarray
- Best Time to Buy and Sell Stock II
- 4Sum
- 3Sum Closest
- Number of Valid Words for Each Puzzle
- Unique Binary Search Trees
- Multiply Strings
- Single Number III
- Longest Common Prefix
- Arranging Coins
- Sum of Left Leaves
- Number of Longest Increasing Subsequence
- Longest Common Subsequence
- Edit Distance
- Delete Operation for Two Strings
- Sum Root to Leaf Numbers
- Integer Break
- Coin Change
- Unique Paths III
- Longest Increasing Subsequence
- Smallest Index With Equal Value
- Minimum Operations to Convert Number
- Flatten a Multilevel Doubly Linked List
- Find the Minimum and Maximum Number of Nodes Between Critical Points
- Plates Between Candles
- Longest Duplicate Substring
- Kth Distinct String in an Array
- Jump Game II
- Roman to Integer
- Number of Unique Paths
- Integer to Roman
- ZigZag Conversion
- Sort Colors
- Letter Combinations of a Phone Number
- Permutations II
- Path Sum II
- Next Permutation
- Invert Binary Tree
- Combination Sum
- Combination Sum II
- Subsets
- Subsets II
- Path Sum
- Min Stack
- Surrounded Regions
- Shortest Path in Binary Matrix
- Next Greater Numerically Balanced Number
- Count Complete Tree Nodes
- Subarray of another tree
- Find Minimum in Rotated Sorted Array II
- Subarray Product Less Than K
- Sort Characters By Frequency
- Find All Anagrams in a String
- Backspace String Compare
- Insert Delete GetRandom O(1)
- Reverse Words in a String
- Interval List Intersections
- Container With Most Water
- Next Greater Element I
- Remove Duplicates from Sorted List
- Remove Duplicates from Sorted List II
- Hand of Straights
- Find Peak Element
- Cyclically Rotating a Grid
- Cousins in Binary Tree
- Angle Between Hands of a Clock
- Simple Bank System
- Search in Rotated Sorted Array
- Search a 2D Matrix
- Path Sum III
- Palindrome Number
- Find First and Last Position of Element in Sorted Array
- Fibonacci Number
- Count Number of Maximum Bitwise-OR Subsets
- Check if Numbers Are Ascending in a Sentence
- String to Integer (atoi)
- Single Number
- Reverse Integer
- Reverse Bits
- Remove Colored Pieces if Both Neighbors are the Same Color
- Minimum Number of Moves to Seat Everyone
- Best Time to Buy and Sell Stock III
- Number of 1 Bits
- House Robber II
- Best Time to Buy and Sell Stock with Cooldown
- Unique Paths
- Unique Paths II
- Triangle
- Perfect Squares
- Minimum Path Sum
- House Robber
- Best Time to Buy and Sell Stock
- Power of Two
- Minimum Size Subarray Sum
- Letter Case Permutation
- Construct Binary Search Tree from Preorder Traversal
- Swap Nodes in Pairs
- Reverse Linked List
- Remove Linked List Elements
- Guess Number Higher or Lower
- Rotting Oranges
- Permutations
- Matchsticks to Square
- Diameter of Binary Tree
- Combinations
- 01 Matrix
- Valid Pair Sum
- Two Out of Three
- Robot Factory
- Populating Next Right Pointers in Each Node
- Permutation in String
- Merge Two Binary Trees
- Median of Two Sorted Arrays
- Computer Game
- Bitwise AND of Numbers Range
- Word Search II
- Two Sum
- Number of Islands
- Merge Two Sorted Lists
- Max Area of Island
- Flood Fill
- Find All Groups of Farmland
- Count Sub Islands
- Add Two Numbers
- Add Two Numbers II
- Longest Substring Without Repeating Characters
- Implement Trie (Prefix Tree)
- Word Search
- Rotate List
- Remove Nth Node From End of List
- Middle of the Linked List
- Reverse Words in a String III
- Reverse String
- Pascal's Triangle
- Pascal's Triangle II
- Find All Duplicates in an Array
- Two Sum II - Input array is sorted
- Sqrt(x)
- Pow(x, n)
- Move Zeroes
- Climbing Stairs
- Squares of a Sorted Array
- Rotate Array
- Find Minimum in Rotated Sorted Array
- Summary Ranges
- Island Perimeter
- Search Insert Position
- Product of Array Except Self
- Merge Triplets to Form Target Triplet
- Maximum difference between increasing elements
- First Bad Version
- Count Number of Pairs With Absolute Difference K
- Sum of Beauty in the Array
- Jump Game
- Binary Search
- Plus one
- Insert new interval in the given intervals