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abulhax
STREAK
715/1432
days
Longest streak/Global longest streak
Language Used
Java, C++, Python
Coding Score
2448
Problem Solved
715
Contest Rating
__
315 points
Contributor
315 points
Contributor
1 Point
Proficient
Proficient
100 Point
Scholar
Scholar
1k Point
Master
Master
10k Point
Ace
Ace
50k Point
184 submissions in current year
SCHOOL (45)
BASIC (11)
EASY (218)
MEDIUM (365)
HARD (76)
- Reverse alternate nodes in Link List
- Reverse a Linked List in groups of given size
- 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
- Delete nodes having greater value on right
- Quick Sort on Linked List
- Insert in Sorted Circular Linked List
- Quick Sort
- Construct Binary Tree from Inorder and Postorder
- Bottom View of Binary Tree
- Intersection Point in Y Shaped Linked Lists
- Diameter of a Binary Tree
- Heap Sort
- Merge two sorted linked lists
- Sum Tree
- Construct Binary Tree from Parent Array
- Tree Boundary Traversal
- Directed Graph Cycle
- Undirected Graph Cycle
- Lowest Common Ancestor in a Binary Tree
- Min distance between two given nodes of a Binary Tree
- Square root of a number
- Max sum path in two arrays
- The Celebrity Problem
- Topological sort
- Vertical Traversal of Binary Tree
- Merge K sorted linked lists
- Find the number of islands
- Max sum in the configuration
- Get Min from Stack
- Serialize and deserialize a binary tree
- Gas Station
- Make Binary Tree From Linked List
- Toeplitz matrix
- Kth element in Matrix
- Is Binary Tree Heap
- Validate an IP Address
- Remove loop in Linked List
- Dijkstra Algorithm
- Distinct occurrences
- Additive sequence
- Largest BST
- Sorted subsequence of size 3
- Multiply two strings
- Implement Atoi
- Maximum Difference
- Palindrome Linked List
- Rat in a Maze Problem - I
- BST with Dead End
- Merge two BST 's
- Root to leaf paths sum
- Bridge edge in a graph
- Find triplets with zero sum
- Duplicate subtree in Binary Tree
- Top View of Binary Tree
- k-th Smallest in BST
- Peak element
- Euler Circuit in an Undirected Graph
- Euler circuit and Path
- Merge Sort on Doubly Linked List
- 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
- Check if Tree is Isomorphic
- Maximum path sum from any node
- Predecessor and Successor
- Check for Children Sum Property in a Binary Tree
- Diagonal sum in binary tree
- Deletion and Reverse in Circular Linked List
- Duplicate Subtrees
- Sum of nodes on the longest path
- Kth Ancestor in a Tree
- ZigZag Tree Traversal
- Vertical Width of a Binary Tree
- Maximum sum of Non-adjacent nodes
- Mother Vertex
- Gray to Binary equivalent
- Smallest Positive Missing Number
- Power Of Numbers
- Maximum occured integer
- Rotate and delete
- Rearrange Array Alternately
- Maximum Index
- Trapping Rain Water
- Stock buy and sell
- Rotate Array
- Kadane's Algorithm
- Majority Element
- Count Inversions
- Two Repeated Elements
- Union of Two Sorted Arrays
- Indexes of Subarray Sum
- Count the number of possible triangles
- Triplet Sum in Array
- Number of pairs
- Level of Nodes
- Make Matrix Beautiful
- Boolean Matrix
- Spirally traversing a matrix
- Search in a sorted Matrix
- Subarray with 0 sum
- Subarray range with given sum
- Sorting Elements of an Array by Frequency
- Longest Consecutive Subsequence
- Case-specific Sorting of Strings
- Evaluation of Postfix Expression
- Stock span problem
- Next Greater Element
- K Sized Subarray Maximum
- Nearly sorted
- 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
- Kth Smallest
- Implement Trie
- Shortest Common Supersequence
- Nth catalan number
- Rotten Oranges
- Maximize The Cut Segments
- Container With Most Water
- Print Anagrams Together
- Rotate by 90 degree
- Closest Three Sum
- Word Break
- Word Search
- Find All Four Sum Numbers
- Paths to reach origin
- Missing And Repeating
- Pascal Triangle
- Maximum Index
- Number of subarrays with maximum values in given range
- Flip Bits
- Top k numbers in a stream
- Longest Span in two Binary Arrays
- Sum of Middle elements of two sorted arrays
- Consecutive 1's not allowed
- Pythagorean Triplet
- Painting the Fence
- Search in Rotated Sorted Array
- Sum of bit differences
- Largest Number formed from an Array
- 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
- Palindrome SubStrings
- Form a palindrome
- Nuts and Bolts Problem
- Longest Subarray with Sum K
- Search Pattern (KMP-Algorithm)
- Shuffle integers
- Find the N-th character
- k largest elements
- Sum of XOR of all pairs
- Find missing in second array
- Longest Common Substring
- Smallest distinct window
- Longest Substring with K Uniques
- Longest Palindrome in a String
- Look and Say Pattern
- K-th element of two Arrays
- K closest elements
- Missing element of AP
- LCS of three strings
- Longest Palindromic Subsequence
- Largest Sum Subarray of Size at least K
- Equalize the Towers
- Minimum sum
- Not a subset sum
- Minimize the Heights II
- Transform to prime
- First and last occurrences of x
- Minimum Deletions
- Print N-bit binary numbers having more 1s than 0s
- Permutations of a String
- Number following a pattern
- Sum of Products
- Unique Number II
- Bleak Numbers
- Modular Exponentiation for large numbers
- Edit Distance
- Game of XOR
- Largest prime factor
- Maximum Tip Calculator
- Modified Game of Nim
- Minimum number of deletions and insertions
- Maximum 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
- Longest subsequence-1
- Power Set
- Count ways to N'th Stair(Order does not matter)
- 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
- Game with String
- Smith Number
- Next Permutation
- Maximum sum of hour glass
- How Many X's?
- Longest Repeating Subsequence
- Longest alternating subsequence
- Left Rotate Matrix K times
- Decode the string
- Total Decoding Messages
- First non-repeating character in a stream
- Check If two Line segments Intersect
- Valid Pair Sum
- 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
- Count all Possible Path
- Find the string in grid
- Count the paths
- Floyd Warshall
- Flood fill Algorithm
- Techfest and the Queue
- Largest subsquare surrounded by X
- Shortest Source to Destination Path
- Divisibility tree
- Police and Thieves
- Recursively remove all adjacent duplicates
- Subset Sum Problem
- Search Pattern (Rabin-Karp Algorithm)
- 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
- Find rectangle with corners as 1
- Paths from root with a specified sum
- Shortest Prime Path
- Insertion Sort for Singly Linked List
- Remove all occurences of duplicates in a linked list
- Minimize the Heights I
- Anti Diagonal Traversal of Matrix
- Unique Number III
- All Unique Permutations of an array
- Course Schedule
- Clone an Undirected Graph
- Min Cost Climbing Stairs
- Overlapping Intervals
- Buy and Sell a Share at most twice
- Reverse a Stack
- Maximum product subset of an array
- K-th Largest Sum Contiguous Subarray
- Maximum Meetings in One Room
- Buy Maximum Stocks if i stocks can be bought on i-th day
- Exactly one swap
- Find shortest safe route in a matrix
- Check if a given graph is tree or not
- Minimum Multiplications to reach End
- Number Of Enclaves
- Eventual 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 II
- Koko Eating Bananas
- Longest subarray with Atmost two distinct integers
- Minimal Cost
- Aggressive Cows
- Smallest Divisor
- Combination Sum II
- Shortest Path in Weighted undirected graph
- 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
- Largest Divisible Subset
- Make array elements unique
- Minimum repeat to make substring
- Prime List
- Water the plants
- Unique Paths in a Grid
- Number of Good Components
- Remove the balls
- Fraction pairs with sum 1
- Minimum Distance Graph
- New Year Resolution
- Grinding Geek
- Flatten BST to sorted list
- Minimize the Difference
- Pairs violating the BST property
- Kth common ancestor in a tree
- Kth Missing Positive Number in a Sorted Array
- Count Subarrays with given XOR
- Set Matrix Zeroes
- Minimum cost to connect all houses in a city
- Meeting Rooms
- Find All Triplets with Zero Sum
- Split array in three equal sum subarrays
- Search in an almost Sorted Array
- Find H-Index
- Longest Subarray with Majority Greater than K
- Count all triplets with given sum in sorted array
- Implement Pow
- K Closest Points to Origin
- Longest Bounded-Difference Subarray
- Lexicographically Largest String After K Deletions
- Group Balls by Sequence
- Reverse a linked list
- Occurence of an integer in a Linked List
- Pairwise swap elements of a linked list
- Given a linked list of 0s, 1s and 2s, sort it.
- Linked list of strings forms a palindrome
- Remove duplicates from an unsorted linked list
- Sorted insert for circular linked list
- Delete node in Doubly Linked List
- Inorder Traversal
- Reverse a Doubly Linked List
- Check for BST
- Right View of Binary Tree
- K distance from root
- Mirror Tree
- Delete without head pointer
- Height of Binary Tree
- Check for Balanced Tree
- Middle of a Linked List
- Left View of Binary Tree
- Delete Middle of Linked List
- Decimal Equivalent of Binary Linked List
- Intersection of two sorted Linked lists
- Find Transition Point
- Remove duplicate element from sorted Linked List
- Level Order in spiral form
- Reverse Level Order Traversal
- DFS of Graph
- Insert a node in a BST
- BFS of graph
- Determine if Two Trees are Identical
- Root to leaf path sum
- Print all nodes that don't have sibling
- Lowest Common Ancestor in a BST
- Largest subarray of 0's and 1's
- Remove duplicates in array
- Binary Tree to BST
- Remove every kth node
- Check if all leaves are at same level
- Multiply two linked lists
- You and your books
- Max distance between same elements
- Print matrix in diagonal pattern
- Check whether BST contains Dead End
- Delete a Node in Single Linked List
- Kth largest element in BST
- Minimum distance between two numbers
- Find duplicates in an array
- Count distinct elements in every window
- Three way partitioning
- Find Common Nodes in two BSTs
- Level order traversal
- Inorder Successor in BST
- Index of an Extra Element
- Insert in a Sorted List
- Split Linked List Alternatingly
- Sum of leaf nodes in BST
- Count More than n/k Occurences
- Symmetric Tree
- Delete Alternate Nodes
- Find the Sum of Last N nodes of the Linked List
- Count Pairs whose sum is equal to X
- Find length of Loop
- Median of BST
- Normal BST to Balanced BST
- Leaf under budget
- Linked List Matrix
- Reverse First K elements of Queue
- Remove Half Nodes
- Closest Neighbour in BST
- Brothers From Different Roots
- Swap the array elements
- Predict the Column
- Xoring and Clearing
- Reverse an Array
- Find first set bit
- Rightmost different bit
- Check whether K-th bit is set or not
- Wave Array
- Frequencies of Limited Range Array Elements
- Equilibrium Point
- Leaders in an array
- Roof Top
- Subarray with given sum
- Print adjacency list
- Sum of upper and lower triangles
- Print Matrix in snake Pattern
- Rotate by 90 degree
- Determinant of a Matrix
- Boundary traversal of matrix
- Anagram
- Winner of an election
- Check if string is rotated by two places
- Strings Rotations of Each Other
- Isomorphic Strings
- Reverse Words
- Panagram Checking
- Non Repeating Character
- Parenthesis Checker
- Minimum Cost of ropes
- N meetings in one room
- Reach a given score
- Count ways to N'th Stair
- Count number of hops
- Union of Arrays with Duplicates
- Missing in Array
- Product array puzzle
- Roman Number to Integer
- Top K Frequent Elements in Array - |
- Sort 0s, 1s and 2s
- Maximize Array Value After Rearrangement
- Pascal Triangle
- Count the elements
- Find the closest number
- Split the Array
- Sorted and Rotated Minimum
- Search in a Row-Column sorted matrix
- Move All Zeroes to End
- Remove all duplicates from a given string
- Chocolate Distribution Problem
- Count pairs Sum in matrices
- Find Pair Given Difference
- Pairs with difference k
- Swap and Maximize
- Bitonic Point
- Single Number
- Alternate positive and negative numbers
- Remaining String
- Kth distance
- Remove Duplicates
- Nearest multiple of 10
- Reorganize The Array
- Facing the sun
- Max Sum without Adjacents
- Second Largest
- Convert array into Zig-Zag fashion
- Two Sum - Pair with Given Sum
- Rotate Bits
- Number of occurrence
- K-Pangrams
- Does array represent Heap
- Modify the Array
- Sum Pair closest to target
- String's Count
- Longest Common Prefix of Strings
- Longest substring with distinct characters
- Substrings with same first and last characters
- Segregate 0s and 1s
- Play With OR
- First element to occur k times
- Find the closest pair from two arrays
- Palindrome String
- Total count
- Pair with given sum in a sorted array
- Print Bracket Number
- Odd Even Problem
- Binary representation of next number
- Padovan Sequence
- Extract the Number from the String
- Minimum Operations
- Check if a number is divisible by 8
- Adding Array Elements
- Find the Highest number
- Armstrong Numbers
- Reverse Bits
- Max Sum Subarray of size K
- Nth Fibonacci Number
- Swap two nibbles in a byte
- Maximum Sum Problem
- Party of Couples
- Maximize dot product
- Shortest path from 1 to n
- Sum of all divisors from 1 to n
- Count numbers containing 4
- Trail of ones
- K-Palindrome
- Reach the Nth point
- Perfect Numbers
- Minimum Cost To Make Two Strings Identical
- Largest number possible
- Recamans sequence
- Compare two fractions
- Form a number divisible by 3 using array digits
- Recursive sequence
- Juggler Sequence
- Summed Matrix
- Row with minimum number of 1's
- Surround the 1's
- Coverage of all Zeros in a Binary Matrix
- Exit Point in a Matrix
- Inorder Traversal and BST
- Letters Collection
- Game of digits
- Rearrange Geek and his Classmates
- Print Pattern
- Array to BST
- Sum of dependencies in a graph
- Find maximum volume of a cuboid
- Smallest window containing 0, 1 and 2
- Insert an Element at the Bottom of a Stack
- Sort a k sorted doubly linked list
- Fibonacci series up to Nth term
- Stock Buy and Sell – Max one Transaction Allowed
- Divisor Game
- Find the first node of loop in linked list
- Weird Island
- Two Smallests in Every Subarray
- Split an array into two equal Sum subarrays
- Largest Pair Sum
- Two Swaps
- Maximize partitions in a String
- Count pairs with given sum
- Count Pairs whose sum is less than target
- Union of Two Sorted Arrays with Distinct Elements
- Intersection of Two arrays with Duplicate Elements
- Find All Triplets with Zero Sum
- Search in a row-wise sorted matrix
- Find Only Repetitive Element from 1 to n-1
- Unique Number I
- Reorder List
- Binary Tree to DLL
- Clone List with Next and Random
- Wildcard Pattern Matching
- Max rectangle
- Subtraction in Linked List
- LRU Cache
- AVL Tree Insertion
- Merge two BST 's
- Alien Dictionary
- Smallest range in K lists
- AVL Tree Deletion
- Nodes at given distance in binary tree
- Fixing Two nodes of a BST
- Maximum Path Sum between 2 Special Nodes
- String Permutations
- Max Circular Subarray Sum
- Merge Without Extra Space
- Smallest window in a string containing all the characters of another string
- Histogram Max Rectangular Area
- Maximum of minimum for every window size
- Find median in a stream
- Solve the Sudoku
- Allocate minimum number of pages
- Minimum Cost Path
- Median of 2 Sorted Arrays of Different Sizes
- Stock Buy and Sell – Multiple Transaction Allowed
- Burning Tree
- Next Smallest Palindrome
- Count Pairs in an Array
- The Painter's Partition Problem-II
- Count Smaller elements
- 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
- Minimum Points To Reach Destination
- Minimum sum partition
- Palindromic Partitioning
- Stock Buy and Sell – Max K Transactions Allowed
- Matrix Chain Multiplication
- Strictly Increasing Array
- Bit Difference
- The Palindrome Pattern
- Nth Natural Number
- Generalised Fibonacci numbers
- Boolean Parenthesization
- Longest valid Parentheses
- Possible Paths in a Tree
- N-Queen Problem
- Brackets in Matrix Chain Multiplication
- Phone directory
- Rohan's Love for Matrix
- Articulation Point - II
- Smallest Positive Integer that can not be represented as Sum
- Find all Critical Connections in the Graph
- Distribute candies in a binary tree
- Split Array Largest Sum
- Find the String
- Kth Smallest Number in Multiplication Table
- Min Chars to Add for Palindrome
- Largest rectangular sub-matrix whose sum is 0
- Vertex Cover
- Maximum Connected group
- Minimize Max Distance to Gas Station
- Candy
- Account Merge
- Better String
- Max min Height
- Geekina Hate 1s
- Making A Large Island
- Meeting Rooms III
- Minimum Weight Cycle
- Check for Binary
- Replace all 0's with 5
- Print the pattern | Set-1
- Palindromic Array
- Print alternate elements of an array
- Print 1 To N Without Loop
- Sum of Array Elements
- Perfect Arrays
- Find Index
- Sum of Array
- Sum of Series
- Print Elements of Array
- At least two greater elements
- Value equal to index value
- Swap kth elements
- Reversing the vowels
- Smaller and Larger
- Remove Spaces
- Display longest name
- Arrays (Sum of array)
- C++ Array (print an element) | Set 2
- Upper case conversion
- Java Arrays | Set 1
- Count of smaller elements
- Convert String to LowerCase
- Reverse a String
- GCD of two numbers
- C++ if-else (Decision Making)
- Addition of Two Numbers
- C++ Input / Output
- Odd or Even
- if-else (Decision Making)
- Java Hello World
- Armstrong Numbers
- Count Digits
- Find the median
- Palindrome
- Sum of Digit is Pallindrome or not
- Reverse digits
- Series AP
- Multiplication Table
- The dice problem
- Print 1 to n without using loops
- Swap two numbers
- nPr
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