- Key Pair
- 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
- Accept the challenge
- Find the Longest Balanced Substring of a Binary String
- Make the Array Beautiful
- Equal Left and Right Subarray Sum
- Remainder on dividing by 11
- Maximize sum
- Array Subset of another array
- Make Array Elements Equal
- Number of Even and Odd Bits
- Minimum Integer
- K Items With the Maximum Sum
- Count the substrings
- Valuable String
- Frogs and Jumps
- Taxi Booking
- Distinct Difference
- Number of Subarrays of 0's
- Count the Number of Vowel Strings in Range
- Count distinct elements in every window
- Symmetric Tree
- Calculate the work done
- Binary matrix having maximum number of 1s
- Max Level Sum in Binary Tree
- Kth Missing Positive Number
- Nice Array
- Alternating Digit Sum
- Common elements
- Number of Valid Words in a Sentence
- Cutting Rectangles
- Intersection of Multiple Arrays
- Reverse both parts
- Left and Right Sum Differences
- Best Poker Hand
- Find Subarrays With Equal Sum
- Unique Paths in a Grid
- Difference Between Element Sum and Digit Sum of an Array
- Count the triplets
- Reverse a String
- Merge Two 2D Arrays by Summing Values
- Find Transition Point
- Maximum Difference by Remapping a Digit
- Finding middle element in a linked list
- 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
- Add to Array-Form of Integer
- Find the Array Concatenation Value
- Count the Number of Fair Pairs
- Count Odd Numbers in an Interval Range
- Arithmetic Number
- Min Jump
- Balloon Everywhere
- Count number of free cell
- Shuffle the Array
- BST Downward Traversal
- Range OR
- Max Sum without Adjacents
- Last cell in a Matrix
- Verifying an Alien Dictionary
- Greatest Common Divisor of Strings
- N-th Tribonacci Number
- Min operations
- All Numbers
- Type it!
- Xenny and Coin Rank
- LCM hates GCD
- Tax in Chefland
- Split The String
- Reach on Time
- Fitness
- Game Points
- Fitness
- Determine the Score
- Chef Plays Ludo
- Burgers
- Audible Range
- Maximum Weight Node
- Remove Outermost Parentheses
- Find the first node of loop in linked list
- Subtract the Product and Sum of Digits of an Integer
- Last Stone Weight
- Find the maximum GCD of the siblings of a Binary Tree
- Ugly Number
- Largest Local Values in a Matrix
- Power of Three
- Palindrome Linked List
- Power of Four
- Sales Analysis III
- Running Sum of 1d Array
- Find Pivot Index
- Min Cost Climbing Stairs
- Duplicate Emails
- Bank Account Summary II
- Actors and Directors Who Cooperated At Least Three Times
- Top Travellers
- Market Analysis I
- Capital Gain/Loss
- Valid Anagram
- The Latest Login in 2020
- Ransom Note
- Game Play Analysis I
- First Unique Character in a String
- Find Total Time Spent by Each Employee
- Customer Placing the Largest Number of Orders
- User Activity for the Past 30 Days I
- Unique Morse Code Words
- Sales Person
- Rising Temperature
- Reshape the Matrix
- Find Followers Count
- Daily Leads and Partners
- Tree Node
- Second Highest Salary
- Rearrange Products Table
- Intersection of Two Arrays II
- Employees With Missing Information
- Customer Who Visited but Did Not Make Any Transactions
- Combine Two Tables
- Article Views I
- Swap Salary
- Recyclable and Low Fat Products
- Patients With a Condition
- Group Sold Products By The Date
- Fix Names in a Table
- Find Customer Referee
- Delete Duplicate Emails
- Customers Who Never Order
- Contains Duplicate
- Calculate Special Bonus
- Big Countries
- Sum of all substrings of a number
- Stickler Thief
- Number of Unique Paths
- Ways to write n as sum
- Reach a given score
- Kadane's Algorithm - II
- Kadane's Algorithm - I
- 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
- Search Query for Strings
- Union-Find
- Number of Connected Components
- N meetings in one room
- Largest number with given sum
- Huffman Decoding
- Activity Selection
- DFS of Graph
- BFS of graph
- Print adjacency list
- Minimum Cost of ropes
- K largest elements
- Binary Heap Operations
- Stack using two queues
- Rotate Deque By K
- Reverse First K elements of Queue
- Queue using two Stacks
- Queue Reversal
- Operations on Queue
- LCA of 3 nodes
- Insertion in deque
- Implement Queue using Linked List
- Implement Queue using array
- Generate Binary Numbers
- Dequeue Traversal
- Deque Implementations
- Deque deletion
- Search a node in a BST
- Print BST elements in given range
- 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
- Find Common Nodes in two BSTs
- Check for BST
- ZigZag Tree Traversal
- 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
- 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 for Balanced Tree
- Removing consecutive duplicates
- Removing consecutive duplicates - 2
- Parenthesis Checker
- Operations on Stack
- 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
- Reverse a linked list
- Pairwise swap of nodes in LinkedList
- Find length of Loop
- Detect Loop in linked list
- Check if Linked List is Palindrome
- 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
- Parenthesis Checker
- Palindrome String
- Convert a sentence into its equivalent mobile numeric keypad sequence
- The Modified String
- Sum of numbers in string
- Reverse words in a given string
- Repeating Character - First Appearance Leftmost
- Remove common characters and concatenate
- Pangram Checking
- Nth number made of prime digits
- Non Repeating Character
- Minimum indexed character
- Maximum Occuring Character
- 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 Isogram or not
- Binary String
- Anagram
- Pattern Search
- Naive Pattern Search
- Winner of an election
- Subarray with 0 sum
- Subarray range with given sum
- Positive Negative Pair
- Numbers containing 1, 2 and 3
- 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
- Sorted matrix
- Rotate by 90 degree
- Reversing the columns of a Matrix
- Print Matrix in snake Pattern
- Multiply the matrices
- Interchanging the rows of a Matrix
- Exchange matrix columns
- Boundary traversal of matrix
- Adding two matrices
- Union of Two Sorted Arrays
- Sort by Absolute Difference
- Number of pairs
- Minimum Difference in an Array
- Kth smallest element
- Intersection of two sorted arrays
- Find triplets with zero sum
- Counting Sort
- Closet 0s 1s and 2s
- Insertion Sort
- Bubble Sort
- Binary Array Sorting
- Subarray with given sum
- Two Repeated Elements
- Roof Top
- Minimum Number in a sorted rotated array
- Floor in a Sorted Array
- Count 1's in binary array
- Wave Array
- Maximum occured integer
- 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 and Second Max
- Array insert at index
- Power Of Numbers
- Missing number in array
- Lucky Numbers
- Josephus problem
- Valid Parentheses
- Linked List Cycle
- Is Subsequence
- Counting Bits
- Excel Sheet Column Number
- Majority Element
- Maximum Depth of Binary Tree
- Add Digits
- Maximum Product of Three Numbers
- Detect Capital
- Add Binary
- Find the Town Judge
- Build an Array With Stack Operations
- Minimum Absolute Difference
- Consecutive Characters
- Element Appearing More Than 25% In Sorted Array
- Find Target Indices After Sorting Array
- Same Tree
- Binary Tree Tilt
- Shift 2D Grid
- Convert Binary Number in a Linked List to Integer
- Minimum Cost to Move Chips to The Same Position
- Minimum Difference Between Highest and Lowest of K Scores
- Number Complement
- Complement of Base 10 Integer
- Uncommon Words from Two Sentences
- Hamming Distance
- Find All Numbers Disappeared in an Array
- Airplane Seat Assignment Probability
- Missing Number
- Word Pattern
- Single Number II
- Isomorphic Strings
- Find the Difference
- Minimum Value to Get Positive Step by Step Sum
- Maximum Subarray
- Longest Common Prefix
- Arranging Coins
- Sum of Left Leaves
- Smallest Index With Equal Value
- Kth Distinct String in an Array
- Roman to Integer
- Number of Unique Paths
- Invert Binary Tree
- Path Sum
- Min Stack
- Subarray of another tree
- Backspace String Compare
- Next Greater Element I
- Remove Duplicates from Sorted List
- Cousins in Binary Tree
- Palindrome Number
- Fibonacci Number
- Check if Numbers Are Ascending in a Sentence
- Single Number
- Reverse Bits
- Minimum Number of Moves to Seat Everyone
- Number of 1 Bits
- Best Time to Buy and Sell Stock
- Power of Two
- Reverse Linked List
- Remove Linked List Elements
- Guess Number Higher or Lower
- Diameter of Binary Tree
- Two Out of Three
- Merge Two Binary Trees
- Computer Game
- Merge Two Sorted Lists
- Flood Fill
- Middle of the Linked List
- Reverse Words in a String III
- Reverse String
- Pascal's Triangle
- Pascal's Triangle II
- Two Sum II - Input array is sorted
- Sqrt(x)
- Pow(x, n)
- Move Zeroes
- Climbing Stairs
- Squares of a Sorted Array
- Summary Ranges
- Island Perimeter
- Search Insert Position
- Maximum difference between increasing elements
- First Bad Version
- Count Number of Pairs With Absolute Difference K
- Binary Search
- Plus one