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184 submissions in current year
SCHOOL (0)
BASIC (31)
EASY (275)
MEDIUM (412)
HARD (96)
- Reverse alternate nodes in Link List
- Rotate a Linked List
- Sort a linked list of 0s, 1s and 2s
- Add Number Linked Lists
- Add 1 to a Linked List Number
- Merge 2 sorted linked list in reverse order
- Detect Loop in linked list
- Quick Sort on Linked List
- Insert in Sorted Circular Linked List
- Check for BST
- Quick Sort
- Binary Tree from Inorder and Postorder
- Bottom View of Binary Tree
- Delete without head pointer
- Intersection in Y Shaped Lists
- Diameter of a Binary Tree
- Merge two sorted linked lists
- Stack using Queue
- Tree Boundary Traversal
- Directed Graph Cycle
- Undirected Graph Cycle
- Lowest Common Ancestor in a BST
- Two Stacks in an Array
- Max sum path in two arrays
- The Celebrity Problem
- Largest subarray with 0 sum
- Topological Sort
- Merge K sorted linked lists
- Find the number of islands
- Max sum in the configuration
- Gas Station
- Wildcard Pattern Matching
- Linked List to Binary Tree
- Is Binary Tree Heap
- Validate an IP Address
- Remove loop in Linked List
- Dijkstra Algorithm
- Additive sequence
- Largest BST
- Sorted subsequence of size 3
- Multiply two strings
- Minimum Swaps to Sort
- Implement Atoi
- Maximum Difference
- Palindrome Linked List
- Print matrix in diagonal pattern
- Rat in a Maze
- BST with Dead End
- Merge two BST 's
- Count distinct elements in every window
- Root to leaf paths sum
- Bridge edge in a graph
- Find triplets with zero sum
- Duplicate Subtree
- Top View of Binary Tree
- k-th Smallest in BST
- Find Common Nodes in two BSTs
- Level order traversal
- Peak element
- Polynomial Addition
- Merge Sort for Linked List
- Euler Circuit in an Undirected Graph
- Euler circuit and Path
- Ancestors in Binary Tree
- Binary Tree to CDLL
- Pair Sum in BST
- Root to Leaf Paths
- Populate Inorder Successor for all nodes
- XOR Linked List
- Counting elements in two arrays
- Linked List that is Sorted Alternatingly
- K Sum Paths
- Leftmost and rightmost nodes of binary tree
- Construct Tree from Inorder & Preorder
- Arrange Consonants and Vowels
- Count the nodes at distance K from leaf
- Vertical sum
- Insert in Sorted way in a Sorted DLL
- Isomorphic Trees
- Maximum path sum
- Predecessor and Successor
- Diagonal sum in binary tree
- Find length of Loop
- Deletion in Circular Linked List
- Normal BST to Balanced BST
- Duplicate Subtrees
- Sum of nodes on the longest path
- ZigZag Tree Traversal
- Vertical Width of a Binary Tree
- Swap Kth nodes from ends
- Maximum Non-Adjacent Nodes Sum
- Mother Vertex
- Gray to Binary Conversion
- Reverse array in groups
- Smallest Positive Missing
- Power Of Numbers
- Maximum occured integer
- Wave Array
- Rotate and delete
- Rearrange Array Alternately
- Maximum Index
- Stock buy and sell
- Rotate Array
- Kadane's Algorithm
- Majority Element
- Count Inversions
- Two Repeated Elements
- Union of 2 Sorted Arrays
- Indexes of Subarray Sum
- Count the number of possible triangles
- Sort by Absolute Difference
- Triplet Sum in Array
- Number of pairs
- Merge Without Extra Space
- Level of Nodes
- Make Matrix Beautiful
- Boolean Matrix
- Spirally traversing a matrix
- Search in a sorted Matrix
- Rotate by 90 degree
- Determinant of a Matrix
- Subarray with 0 sum
- Subarray range with given sum
- Sort Elements by Decreasing Frequency
- Longest Consecutive Subsequence
- Strings Rotations of Each Other
- Case-specific Sorting of Strings
- Postfix Evaluation
- Stock span problem
- Next Greater Element
- K Sized Subarray Maximum
- Minimum Cost of ropes
- Nearly sorted
- Find median in a stream
- Activity Selection
- Fractional Knapsack
- Job Sequencing Problem
- Minimum Platforms
- Largest number in K swaps
- Minimum Jumps
- Detect Cycle using DSU
- Stickler Thief
- Ways to Reach the n'th Stair
- Optimal Strategy For A Game
- Sum of all substrings of a number
- Longest Increasing Subsequence
- Longest Common Subsequence
- 0 - 1 Knapsack Problem
- Lucky Numbers
- Allocate Minimum Pages
- Zero Sum Subarrays
- Kth Smallest
- Implement Trie
- Shortest Common Supersequence
- Rotten Oranges
- Maximize The Cut Segments
- Print Anagrams Together
- Rotate by 90 degree
- Top K Frequent in Array
- Closest Three Sum
- Word Break
- Stock Buy and Sell – Multiple Transaction Allowed
- 4 Sum - All Quadruples
- Sort 0s, 1s and 2s
- Paths to reach origin
- Pascal Triangle
- Maximum Index
- Number of subarrays with maximum values in given range
- Top k numbers in a stream
- Longest Span in two Binary Arrays
- Maximize Number of 1's
- Sum of Middle elements of two sorted arrays
- Consecutive 1's not allowed
- Pythagorean Triplet
- Painting the Fence
- Pair Sum Closest to 0
- Search in Rotated Sorted Array
- Count pairs Sum in matrices
- Sum of bit differences
- Max Score from Subarray Mins
- Form the Largest Number
- Add Binary Strings
- Maximum Product Subarray
- Longest subarray with sum divisible by K
- Check if a string is repetition of its substring of k-length
- Sort the given array after applying the given equation
- Row with max 1s
- Swapping pairs make sum equal
- Check if frequencies can be equal
- Column name from a given column number
- Substrings with K Distinct
- Form a palindrome
- Nuts and Bolts Problem
- Longest Subarray with Sum K
- Cutting Binary String
- Max Sum without Adjacents
- Shuffle integers
- Find the N-th character
- k largest elements
- Sum of XOR of all pairs
- Longest Common Substring
- Smallest distinct window
- Longest substring with distinct characters
- Longest Substring with K Uniques
- Longest Palindrome in a String
- Look and Say Pattern
- Product Pair
- Valid Expression
- K-th element of two Arrays
- Triplets with Smaller Sum
- K closest elements
- Missing element of AP
- Minimum swaps and K together
- LCS of three strings
- Longest Palindromic Subsequence
- Largest Sum Subarray of Size at least K
- First negative in every window of size k
- Equalize the Towers
- Minimum sum
- Not a subset sum
- Minimize the Heights II
- Transform to prime
- First and Last Occurrences
- Palindrome in Alphanumeric String
- Minimum Deletions
- Maximum Product of Increasing Subsequence of Size 3
- Print N-bit binary numbers having more 1s than 0s
- Nine Divisors
- Permutations of a String
- Number following a pattern
- Sum of Products
- Unique Number II
- Bleak Numbers
- Modular Exponentiation
- Game of XOR
- Modified Game of Nim
- Minimum number of deletions and insertions
- Maximize dot product
- Max Sum Increasing Subsequence
- Minimum cost to fill given weight in a bag
- Coin Change (Count Ways)
- Sequence of Sequence
- String Subsequence
- Mobile numeric keypad
- Gold Mine Problem
- Coin Change (Minimum Coins)
- Dice throw
- Perfect Sum Problem
- Smallest number
- Trail of ones
- K-Palindrome
- Longest subsequence-1
- Power Set
- Count ways to N'th Stair(Order does not matter)
- Minimum Cost To Make Two Strings Identical
- Knapsack with Duplicate Items
- nCr
- Geek and its Game of Coins
- Minimum steps to destination
- Partition Equal Subset Sum
- Count possible ways to construct buildings
- Count digit groupings of a number
- Array Pair Sum Divisibility Problem
- Prime Pair with Target Sum
- Number of paths
- Nth Natural Number
- Number of paths in a matrix with k coins
- Return two prime numbers
- Game with String
- Smith Number
- Next Permutation
- Maximum sum of hour glass
- How Many X's?
- Exit Point in a Matrix
- Longest alternating subsequence
- Decode the string
- Total Decoding Messages
- Print leaf nodes from preorder traversal of BST
- Number of Rectangles in a Circle
- Largest square formed in a matrix
- Integral Points Inside Triangle
- Transitive closure of a Graph
- Replace O's with X's
- Rohan's Love for Matrix
- Find the string in grid
- Count the paths
- Floyd Warshall
- Flood fill Algorithm
- Techfest and the Queue
- Largest subsquare surrounded by X
- Divisibility tree
- Police and Thieves
- Jump Game
- Subset Sum Problem
- All Palindromic Partitions
- Bellman-Ford
- Subarrays with sum K
- Coin Piles
- Remove K Digits
- Substrings of length k with k-1 distinct elements
- Maximum XOR of two numbers in an array
- Construct list using given q XOR queries
- Find duplicate rows in a binary matrix
- Maximum sum of elements not part of LIS
- Find rectangle with corners as 1
- Paths from root with a specified sum
- Shortest Prime Path
- Sort for Singly Linked List
- Remove all occurences of duplicates in a linked list
- Minimize the Heights I
- Anti Diagonal Traversal of Matrix
- IPL 2021 - Match Day 2
- Unique Number III
- All Unique Permutations of an array
- Course Schedule II
- Clone an Undirected Graph
- Min Cost Climbing Stairs
- Overlapping Intervals
- Maximum product subset of an array
- K-th Largest Sum Contiguous Subarray
- Maximum Meetings in One Room
- Buy Maximum Stocks
- Exactly one swap
- Find shortest safe route in a matrix
- Minimum Cost to cut a board into squares
- Graph is Tree or Not
- Next element with greater frequency
- Sort a k sorted doubly linked list
- Minimum Multiplications to reach End
- Number Of Enclaves
- Safe States
- City With the Smallest Number of Neighbors at a Threshold Distance
- Path With Minimum Effort
- Shortest Path in Undirected Graph
- Shortest path in Directed Acyclic Graph
- Majority Element - More Than n/3
- Koko Eating Bananas
- Longest subarray with Atmost two distinct integers
- Sum of subarray minimums
- Minimal Cost
- Aggressive Cows
- Smallest Divisor
- Combination Sum Without Repetition
- Shortest Path in Weighted undirected graph
- Minimum days to make M bouquets
- Minimum Absolute Difference In BST
- Maximum Sum Combination
- Non-overlapping Intervals
- Stickler Thief II
- Insert Interval
- Longest String Chain
- Partitions with Given Difference
- Floor in BST
- Number of unique flavors of candies
- Largest Divisible Subset
- Make array elements unique
- Next Greater Element in Circular Array
- Find the first node of loop in linked list
- Find the longest string
- Minimum repeat to make substring
- Prime List
- Water the plants
- Remove the balls
- Empty the String
- Score of Array
- Subtree with k primes
- Geeks Like You
- New Year Resolution
- Grinding Geek
- Collecting Coins
- Flatten BST to sorted list
- Last Fairy Standing
- Minimize the Difference
- Maximum Bridges
- Minimize the Array
- Pairs violating the BST property
- Kth common ancestor in BST
- Get Count
- Kth Missing Positive Number in a Sorted Array
- Count Subarrays with given XOR
- Set Matrix Zeros
- Minimum cost to connect all houses in a city
- Palindromic Substrings
- Count pairs with given sum
- Find All Triplets with Zero Sum
- Split array in three equal sum subarrays
- Search in an almost Sorted Array
- Find H-Index
- Subset XOR
- Longest Subarray with Majority Greater than K
- Count all triplets with given sum in sorted array
- Balancing Consonants and Vowels Ratio
- Implement Pow
- Subarrays With At Most K Distinct Integers
- Minimum Sum
- Longest Bounded-Difference Subarray
- Unique Node Counts
- Perfect Square Difference
- Longest Even-Length Subsequence
- Divisible by 13
- Lexicographically Largest String After K Deletions
- Group Balls by Sequence
- Count Unique Vowel Strings
- Count Numbers Containing Specific Digits
- 2D Difference Array
- Difference Check
- Farthest Smaller Right
- Maximize the minimum difference between k elements
- Search in fully rotated sorted 2D matrix
- String stack
- Sum of Nodes in BST Range
- Construct Tree from Preorder & Postorder
- Reverse a linked list
- Frequency in a Linked List
- Pairwise swap elements of a linked list
- Linked list of strings forms a palindrome
- Delete nodes having greater value on right
- Remove duplicates from an unsorted linked list
- Delete in a Doubly Linked List
- Inorder Traversal
- Reverse a Doubly Linked List
- Bubble Sort
- Selection Sort
- Insertion Sort
- Right View of Binary Tree
- K distance from root
- Mirror Tree
- Maximum Width of Tree
- Height of Binary Tree
- Balanced Tree Check
- Kth from End of Linked List
- Middle of a Linked List
- Left View of Binary Tree
- Delete Middle of Linked List
- Decimal Equivalent of Binary Linked List
- Intersection Sorted Linked Lists
- Find Transition Point
- Queue using two Stacks
- Remove Duplicates from a Sorted Linked List
- Postorder Traversal
- Level Order in spiral form
- Reverse Level Order Traversal
- DFS of Graph
- Insert a node in a BST
- BFS of graph
- Identical Trees
- Root to leaf path sum
- Square Root
- Nodes without a Sibling
- Binary Search
- Run Length Encoding
- Remove Duplicates Sorted Array
- Remove Duplicates from an array
- Binary Tree to BST
- Toeplitz matrix
- Remove every k'th node
- Leaves at Same Level or Not
- Multiply two linked lists
- You and your books
- Max distance between same elements
- Delete in a Singly Linked List
- Kth largest element in BST
- Minimum distance in an Array
- Array Duplicates
- Three way partitioning
- Inorder Successor in BST
- Index of an Extra Element
- Insert in a Sorted List
- Split Linked List Alternatingly
- Minimum element in BST
- Sum of leaf nodes in BST
- More than n/k Occurrences
- Reverse Using Stack
- Symmetric Tree
- Delete Alternate Nodes
- Find the Sum of Last N nodes of the Linked List
- Count Pairs whose sum is equal to X
- Leaf under budget
- Linked List Matrix
- Reverse first K of a Queue
- Remove Half Nodes
- Closest Neighbour in BST
- Find Sum Pairs Across Two BSTs
- Move all zeros to the front of the linked list
- Delete Mid of a Stack
- Step by Step Condition - Java
- Swap the array elements
- Predict the Column
- Xoring and Clearing
- Reverse an Array
- Frequency Game
- First Set Bit
- Rightmost different bit
- Check K-th Bit
- Power of 2
- Frequencies in a Limited Array
- Equilibrium Point
- Array Leaders
- Floor in a Sorted Array
- Minimum Number in a sorted rotated array
- Roof Top
- Print adjacency list
- Sum of upper and lower triangles
- Print Matrix in snake Pattern
- Matrix Boundary Traversal
- Anagram
- Winner of an election
- String Rotated by 2 Places
- Isomorphic Strings
- The Modified String
- Reverse Words
- Minimum indexed character
- Panagram Checking
- Non Repeating Character
- Parenthesis Checker
- Minimum indexed character
- N meetings in one room
- Reach a given score
- Count ways to N'th Stair
- Count number of hops
- First Repeating Element
- Union of Arrays with Duplicates
- Check Equal Arrays
- Missing in Array
- Product array puzzle
- Roman Number to Integer
- Intersection of Arrays with Distinct
- Max Value Permutation
- Missing And Repeating
- Non-Repeating Element
- Count the elements
- Find Kth Rotation
- Find the closest number
- Maximize sum after K negations
- Common in 3 Sorted Arrays
- Sorted and Rotated Minimum
- Maximum no of 1's row
- Search in a Row-Column sorted matrix
- Move All Zeroes to End
- String Duplicates Removal
- Chocolate Distribution Problem
- Count the triplets
- Find Pair Given Difference
- Swap and Maximize
- Bitonic Point
- Smallest subarray with sum greater than x
- Single Number
- Alternate Positive Negative
- Remaining String
- Check if a given string is a rotation of a palindrome
- Remove b and ac from a given string
- Kth distance
- Palindrome Sentence
- Arya's Long String
- Remove Duplicates
- Same characters in two strings
- Nearest multiple of 10
- Reorganize The Array
- Facing the sun
- Second Largest
- Convert array into Zig-Zag fashion
- Two Sum - Pair with Given Sum
- Rotate Bits
- Second most repeated string in a sequence
- Find all pairs with a given sum
- Number of occurrence
- K-Pangrams
- Does array represent Heap
- Modify the Array
- Check if array is sorted
- Sum Pair closest to target
- Find missing in second array
- String's Count
- Longest Common Prefix of Strings
- Special array reversal
- Substrings with same first and last characters
- Two sum -Pairs with 0 Sum
- Segregate 0s and 1s
- Play With OR
- Tywin's War Strategy
- At Least K Occurrences
- Find the closest pair from two arrays
- Count the Zeros
- Merge two binary Max heaps
- Four Elements
- Palindrome String
- Total count
- Pair with given sum in a sorted array
- Pattern Searching
- Print Bracket Number
- Divisible by 7
- Shop in Candy Store
- Odd Even Problem
- Largest number in one swap
- Is Binary Number Multiple of 3
- Padovan Sequence
- Extract the Number from the String
- Minimum Operations
- Divisibility by 8
- Number of 1 Bits
- Find the Highest number
- Armstrong Numbers
- Reverse Bits
- Max Sum Subarray of size K
- Nth Fibonacci Number
- Swap two nibbles in a byte
- Count Digits
- Prime Number
- Maximum Sum Problem
- Shortest path from 1 to n
- Sum 1 to n Divisors
- Assign Mice Holes
- Reach the Nth point
- Minimum number of Coins
- Perfect Numbers
- Largest number possible
- Recamans sequence
- The Palindrome Pattern
- Compare two fractions
- Form a number divisible by 3 using array digits
- Recursive sequence
- Summed Matrix
- Arithmetic Number
- Row with Minimum 1s
- Surround the 1's
- Coverage of all Zeros in a Binary Matrix
- Inorder Traversal and BST
- Letters Collection
- Print Pattern
- Sum of dependencies in a graph
- Find maximum volume of a cuboid
- Check if a String is Subsequence of Other
- First and last occurrences of x
- Smallest window containing 0, 1 and 2
- Insert an Element at the Bottom of a Stack
- Fibonacci series up to Nth term
- Stock Buy and Sell – Max one Transaction Allowed
- Divisor Game
- Remove duplicates from a sorted doubly linked list
- Make the array beautiful
- Remainder on dividing by 11
- Lower Case to Upper Case
- High Frequency
- Weird Island
- Construction of a string
- Virus Infection
- Same characters
- Find Bots on Geeklandster
- Build Adjacency List
- Strong Students in School
- Min Query
- The Final Task
- Divide and Rule
- Maximum Happiness
- MAX Array
- Illuminate the hall
- Magic Array
- Not a palindromic string
- Minimum Number of Elements
- Eye's Contact
- Two Smallests in Every Subarray
- Split an array into two equal Sum subarrays
- Largest Pair Sum
- Good Substrings
- Minimize Cost
- Winner Team
- Maximum Sum
- Geek String
- Distribute Balls
- Two Swaps
- Maximize partitions in a String
- Meeting Rooms
- Count Pairs whose sum is less than target
- Union of Two Sorted Arrays with Distinct Elements
- Intersection of Two arrays with Duplicate Elements
- Search in a row-wise sorted matrix
- Find Only Repetitive Element from 1 to n-1
- Seating Arrangement
- Bitwise Operations
- Longest Substring
- Books Reordering
- Maximum Score
- Unique Number I
- Find Total Pairs
- Maximum Value Subsequence
- Maximum Value
- Product Modulo Check
- Linked List Group Reverse
- Reorder List
- Binary Tree to DLL
- Clone List with Next and Random
- Min distance between two given nodes of a Binary Tree
- Serialize and deserialize a binary tree
- Max rectangle
- Subtraction in Linked List
- Distinct occurrences
- LRU Cache
- AVL Tree Insertion
- Longest Palindromic Substring in Linear Time
- Alien Dictionary
- Smallest range in K lists
- AVL Tree Deletion
- Merge Sort on Doubly Linked List
- Nodes at given distance in binary tree
- Fixing Two nodes of a BST
- Trapping Rain Water
- Max Circular Subarray Sum
- Smallest window containing all characters
- Histogram Max Rectangular Area
- Solve the Sudoku
- Minimum Cost Path
- Word Ladder I
- Median of 2 Sorted Arrays of Different Sizes
- Burning Tree
- Next Smallest Palindrome
- The Painter's Partition Problem-II
- Palindrome SubStrings
- Search Pattern
- Count Smaller elements
- Largest rectangle of 1s with swapping of columns allowed
- Longest Prefix Suffix
- Number of distinct subsequences
- Wildcard string matching
- Circle of strings
- Longest repeating and non-overlapping substring
- Sum-string
- Sub-arrays with equal number of occurences
- Edit Distance
- Minimum Points To Reach Destination
- Minimum sum partition
- Palindromic Partitioning
- Next Happy Number
- Stock Buy and Sell – Max K Transactions Allowed
- Matrix Chain Multiplication
- Strictly Increasing Array
- Bit Difference
- Median in a row-wise sorted Matrix
- Generalised Fibonacci numbers
- Boolean Parenthesization
- Longest valid Parentheses
- Possible Paths in a Tree
- N-Queen Problem
- Brackets in Matrix Chain Multiplication
- Articulation Point - II
- Word Wrap
- Maximum sum Rectangle
- Smallest Positive Integer that can not be represented as Sum
- Search Pattern (Rabin-Karp Algorithm)
- Find all Critical Connections in the Graph
- Sorted Linked List to BST
- Count occurrences of a given word in a 2-d array
- Reverse a sublist of a linked list
- Distribute Candies
- IPL 2021 - Final
- Split Array Largest Sum
- Scrambled String
- Find the String
- Kth Smallest Number in Multiplication Table
- Stock Buy and Sell – Max 2 Transactions Allowed
- Min Chars to Add for Palindrome
- Largest rectangular sub-matrix whose sum is 0
- Vertex Cover
- Maximum Connected group
- Expression Add Operators
- MaxSkill
- Minimum Cost to Merge Stones
- Minimize Max Distance to Gas Station
- Count Reverse Pairs
- Candy
- Account Merge
- Better String
- Fixing Two swapped nodes of a BST
- Maximum Number of coins
- Cake Distribution Problem
- Geekina Hate 1s
- Making A Large Island
- Stable Array
- Minimum k for Valid XOR Combinations
- Meeting Rooms III
- Minimum Weight Cycle
- Longest Periodic Proper Prefix
- Maximum Non-Overlapping Odd Palindrome Sum
- Sum of Mode
- Find Length of Linked List
- Linked List Insertion At End
- Is Linked List Length Even?
- Triplet Family
- Array Search
- Sorted Array Search
- Reverse a String
- First n Fibonacci
- Sum of Natural Numbers
- Alternative Sorting
- Value equal to index value
- Largest Element in Array
- Rotate Array by One
- Array Subset
- Min and Max in Array
- Maximum average among all subarrays
- Small Sum
- Pattern 5
- Pattern 6
- Pattern 7
- Pattern 8
- Pattern 10
- Pattern 13
- Data Type
- Naughty Geek
- Isomorphic Strings
- Naughty Geek
- Valid Strings
- Time Travel
- Disk Placement
- Difference Sum