154 Problems
215 Problems
105 Problems
Delete the Node at a Particular Position in a Linked List
The Deepest Node
Pascal's Triangle
Repeated Elements in an Array
Rotate a Square Image Counterclockwise
Iterative BST Validation
Anagrams
Find the Maximum BST Node
Distance of a node from the root
Couple Sum
Replace all Spaces
Maximum Sum Path
Find the Lowest Common Ancestor of Two Tree Nodes
Selection Sort
Boggle with Paper Dictionary
Even or Odd?
Jam into a BST
Making Change
Horizontal Flip
Binary Search on Array of Integers
Find the Transpose of a Square Matrix
Full Tree Decompression
Delete a Circular-Linked List's Tail Node
Find the Number that Appears Once
Power of 2
Find the Level that has the Maximum Sum
Snake
Unique Chars in a String
Delete a List's Head Node
Delete the Node at the Specific Position in a Doubly Linked List
Mobile Game Range Module - Merging Ranges
Does an Element N Exist in a Given Binary Tree?
Recursive Preorder Traversal
Natural Language Parser
Print all Possible Characters
Insert a Node at the Head in a Doubly Linked List
Permutations!
Bit Conversion
Even Split
Find the Diameter of a BST
Generate Combinations of Parentheses
Combinations and Permutations
Implement the Djikstra Shortest Path Algorithm in a Graph
Find the Sum of all Elements in a Binary Tree Iteratively
Recursive String Permutation
Find the N^{th} Node from the End - Linked List
Count Paths on a Game Board
Insert a Node at the Tail of a Doubly Linked List
Insert a Node at the Head of a Circular Linked List
Delete the Node at the Head of a Doubly Linked List
Delete the Tail Node of a Doubly Linked List
POW!
Looping Lists : Space complexity O(n)
Introduction to Tries
Remove the "N^{th} from the end" Node from a Singly-Linked List
Minimum Sum Path in a Triangle
Boggle with Electronic Dictionary
Recursive Inorder Traversal
Recursive Postorder Traversal
Iterative Postorder Traversal
Roll the Dice!
Parse Simple Mathematical Expressions
Add Two Linked List-ish Numbers
Iteratively, find the Max Element in a Give Binary Tree
Height of a Binary Tree
Mobile Game Range Module - Inserting Ranges
Largest Square
Find the k^{th} Smallest Node in a BST
Find a BST Node
Insert a Node at the End of a Linked List
String Compression
Find the Max Element in a Binary Tree Recursively
Implement the Breadth First Search Algorithm for a Graph
Levelorder Traversal
Max Gain
Find the Missing Number in a Set of Numbers from 1 to 10
Subset Summation
Image Manipulation
Distance between two nodes in a Binary Tree
Delete the Head Node of a Circular Linked List
Minimum Sum Path
Recovering IPv4 Addresses
Flip bits in a matrix
Array Partition
Maximum Coordinates!
Are these Binary Trees Identical?
Boggle Search
Remove Duplicates from a List of Words
Subset Summation with Number Constraint
Print a Binary Tree Level by Level
Insert a Node at the Front of a Linked List
Find the Maximum Number of Repetitions
BST Validation
Matrix Max Sum Path with Dynamic Programming
Graph Depth First Search
Reverse Level Order Traversal
Remove Duplicate Nodes
Implement the Depth First Search traversal Algorithm in a Grap
Count the Leaves!
Implement Breadth First Search Traversal Algorithm in a Grap
Reverse Words with Punctuation
Implement a Least Recently Used (LRU) Cache
Binary Tree Subsets with Same Sum
Balanced Braces
Count 1
s in a Binary Representation
Knapsack Algorithm
Merge Two Sorted Integer Arrays in Linear Time
Addition of Binary Strings
Iterator of Binary Search Tree with Nodes Containing Integer Data
Day with Maximum Difference in Temperatures
Soccer Team with Minimum Difference in Goals
Path between Two Input Words in a Dictionary
A million lines of code!
Tail N Number of Lines from an Input File
Add Two Numbers without using Plus Sign
Integer to Roman
Longest Consecutive Integers Set in an Array
Multiplication of Arrays
First N Prime Numbers
Rotate an Array to the Right.
Duplicate neighbours
Tail word length
Dominant Element
Merge Integer Ranges
Insert and Merge Ranges
Look and Say Sequence
Triple Sum
Quadruple Sum
Find Needle in a Haystack
Minimum Sub Array Size for a Target
Make Palindrome
Sum Root-to-Leaf Numbers
Range of a Number in an Array
Rightmost Nodes of a Tree
Fraction to Decimal
Excel - Column Name to Number
Excel - Column Number to Column Name
Chocolate time!
Unique Routes!
Break a Word!
Sorted Linked List into BST
Evaluate Postfix Notation
Decode Numbers!
Circular route
Minimum Window Sequence
Validate a Sudoku
Robbery
Division
Longest Common Prefix in a group of Strings
Wildcard Pattern Matching
Binary Gap
Repeated Sequences(DNA)
Minimum Depth of a Tree
Merge array into the Largest Number
Minimum number of Jumps
Longest substring with two Unique Characters
Simplify file Path
Sorted Array into BST
Compare Two Versions
Re-arrange Linked List in Pairs
Is this Integer a Palindrome?
Iterative Inorder Traversal
Longest Non-Repeating Substring
N-Ary Tree Serialization
Binary Tree Serialization
HashMap with Random Value Picker
Find the First Non Duplicate Character in a String
Number of Full Nodes in a Binary Tree
Find the Sum of all Elements in a Binary Tree
Check Balanced Parentheses
Reverse a Linked List in Pairs
Binary Representation
Find the k^{th} Largest Node in a BST
Check a Linked List for Loops or Cycles With O(1) Space Complexity
Delete a List's Tail Node
Fibonacci Number
Insert a Node at the Specified Position in Doubly Linked List
Is this List a Palindrome?
Find the Maximum Contiguous Subsequence in an Array
Find a Node in a Binary Tree Without Using Recursion
Number of Half Nodes in a Binary Tree
Stock Market Oracle
Insert a Node at the Tail of a Circular Linked List
Find the size of the Binary Tree
Reverse a string
Rotate a Square Image Clockwise
Fill in the Ancestors of the Node in a Binary Tree
Insert Stars
Longest Palindromic Substring
Word Similarity - Edit Distance
Print Paths
Rotate Linear Array
Merge Two Sorted Arrays
Insert a Node at a specified position in a Linked List
Steal the Node
Isomorphic Strings
Reverse a Singly Linked List
Flip it!
Palindrome Tester
Mirror Mirror on the Wall ...
Print all Nodes in the Range a .. b in a given BST
Matrix Max Sum Path with DFS
Reverse an Integer
1-800-PROBLEM
Find the Minimum BST Node
Merge k Sorted Linked Lists
Find the Middle of a List in a Single Pass
Find the N^{th} Node from the end without using extra memory - Linked List
Better Fibonacci
Bit Swapping
Iterative Preorder Traversal
Convert a Binary Tree to its Mirror Image
Recursively Merge Two Sorted Linked Lists
Happy Numbers!
Bubble Sort
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