- Key Pair
- Count Pairs With Given Sum
- Wifi Range
- Antique Collections
- Dominant Pairs
- Maximum Length
- Accept the challenge
- Make the Array Beautiful
- Add minimum characters
- Equal Left and Right Subarray Sum
- Count Special Numbers
- Minimum Steps Required
- Remainder on dividing by 11
- Maximize sum
- Array Subset of another array
- Array Pair Sum Divisibility Problem
- Make Array Elements Equal
- Minimum Integer
- Count the substrings
- Shy Geek
- Valuable String
- Frogs and Jumps
- Taxi Booking
- Shortest XY distance in Grid
- Distinct Difference
- Number of Subarrays of 0's
- Count distinct elements in every window
- Maximum Possible Value
- Make array beautiful
- Calculate the work done
- Binary matrix having maximum number of 1s
- Yet another query problem
- Maximum Triplet product
- Find anagrams in linked list
- Max Level Sum in Binary Tree
- Longest Common Substring
- Geek hates too many 1s
- Save Flowers
- Nice Array
- Avoid Fire
- Kth smallest element
- Find Missing And Repeating
- Common elements
- Best Node
- Cutting Rectangles
- Walls Coloring II
- Update Queries
- Optimal Array
- Reverse both parts
- Get minimum element from stack
- Number of Good Components
- Valid Compressed String
- Implement Atoi
- Unique Paths in a Grid
- Count the triplets
- Connect Nodes at Same Level
- Reverse a String
- Multiply two strings
- Fill the Matrix
- Find Transition Point
- Count Cyclic Paths
- Fixing Two Swapped nodes of a BST
- Finding middle element in a linked list
- Binary Search
- Apple Sequences
- Is it Fibonacci
- Find duplicates in an array
- Good Stones
- Geeks Island
- Walls Coloring
- Arithmetic Number
- Prime List
- Min Jump
- Minimum Days
- Balloon Everywhere
- Maximum Bipartite Matching
- Count number of free cell
- Length of the longest subarray with positive product
- BST Downward Traversal
- Range OR
- Mex Array
- Equal grouping
- Max Sum without Adjacents
- Last cell in a Matrix
- Largest Sum Cycle
- Distinct Coloring
- Minimum times A has to be repeated such that B is a substring of it
- Select Nodes
- Min operations
- All Numbers
- Scrambled String
- Total Decoding Messages
- Type it!
- Convert an array to reduced form
- Split The String
- Next Greater Element
- Minimum Operations
- Geeks And The String
- GCD Array
- Minimum X (xor) A
- Maximum Weight Node
- Carpet into Box
- Find the first node of loop in linked list
- Find the maximum GCD of the siblings of a Binary Tree
- Merging Details
- Sum of two large numbers
- Longest Sub-Array with Sum K
- Knight Walk
- Number of Turns in Binary Tree
- Max length chain
- Unique BST's
- Sum of all substrings of a number
- Stickler Thief
- Shortest Common Supersequence
- 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
- 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
- Valid Pair Sum