154 Problems
215 Problems
105 Problems
Find the Maximum BST Node
Find the k^{th} Smallest Node in a BST
Delete a List's Head Node
Boggle with Paper Dictionary
Delete a Circular-Linked List's Tail Node
Rotate a Square Image Clockwise
Insert a Node at the Tail of a Circular Linked List
Number of Full Nodes in a Binary Tree
Remove Duplicates from a List of Words
BST Validation
String Compression
Flip it!
Remove the "N^{th} from the end" Node from a Singly-Linked List
Find the Level that has the Maximum Sum
Number of Half Nodes in a Binary Tree
Permutations!
Find a Node in a Binary Tree Without Using Recursion
Levelorder Traversal
Fill in the Ancestors of the Node in a Binary Tree
Find the Sum of all Elements in a Binary Tree
Anagrams
Full Tree Decompression
Find the Middle of a List in a Single Pass
Find the Maximum Number of Repetitions
Iteratively, find the Max Element in a Give Binary Tree
Repeated Elements in an Array
Insert a Node at the Front of a Linked List
Print Paths
Reverse an Integer
Does an Element N Exist in a Given Binary Tree?
Natural Language Parser
Print all Possible Characters
Add Two Linked List-ish Numbers
Longest Palindromic Substring
Selection Sort
Binary Search on Array of Integers
Are these Binary Trees Identical?
Find the N^{th} Node from the end without using extra memory - Linked List
Happy Numbers!
Insert a Node at the Specified Position in Doubly Linked List
Subset Summation
Delete the Head Node of a Circular Linked List
Matrix Max Sum Path with DFS
Count the Leaves!
Height of a Binary Tree
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
Steal the Node
Recursive Inorder Traversal
Recursive Postorder Traversal
Iterative Postorder Traversal
Reverse Level Order Traversal
Roll the Dice!
Insert a Node at a specified position in a Linked List
Parse Simple Mathematical Expressions
Print all Nodes in the Range a .. b in a given BST
Palindrome Tester
Print a Binary Tree Level by Level
Reverse a string
Rotate a Square Image Counterclockwise
Mirror Mirror on the Wall ...
Find the Diameter of a BST
Recovering IPv4 Addresses
Find a BST Node
POW!
Combinations and Permutations
Iterative BST Validation
Pascal's Triangle
Generate Combinations of Parentheses
Boggle Search
Insert a Node at the End of a Linked List
Maximum Sum Path
Max Gain
Couple Sum
1-800-PROBLEM
Reverse a Singly Linked List
Find the Sum of all Elements in a Binary Tree Iteratively
Flip bits in a matrix
Iterative Inorder Traversal
Minimum Sum Path
Even Split
Array Partition
Find the Minimum BST Node
Maximum Coordinates!
Find the Max Element in a Binary Tree Recursively
Better Fibonacci
Count Paths on a Game Board
Even or Odd?
Minimum Sum Path in a Triangle
Find the N^{th} Node from the End - Linked List
Fibonacci Number
Insert Stars
Graph Depth First Search
Implement the Depth First Search traversal Algorithm in a Grap
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)
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
Longest Non-Repeating Substring
Find the k^{th} Largest Node in a BST
N-Ary Tree Serialization
HashMap with Random Value Picker
Check Balanced Parentheses
Delete a List's Tail Node
The Deepest Node
Check a Linked List for Loops or Cycles With O(1) Space Complexity
Horizontal Flip
Mobile Game Range Module - Merging Ranges
Implement the Breadth First Search Algorithm for a Graph
Stock Market Oracle
Find the Missing Number in a Set of Numbers from 1 to 10
Subset Summation with Number Constraint
Find the Maximum Contiguous Subsequence in an Array
Find the Transpose of a Square Matrix
Is this Integer a Palindrome?
Distance between two nodes in a Binary Tree
Is this List a Palindrome?
Rotate Linear Array
Boggle with Electronic Dictionary
Delete the Node at a Particular Position in a Linked List
Find the size of the Binary Tree
Iterative Preorder Traversal
Implement the Djikstra Shortest Path Algorithm in a Graph
Making Change
Find the Lowest Common Ancestor of Two Tree Nodes
Unique Chars in a String
Binary Tree Serialization
Recursive Preorder Traversal
Minimum Depth of a Tree
Find the First Non Duplicate Character in a String
Merge k Sorted Linked Lists
Delete the Node at the Specific Position in a Doubly Linked List
Insert a Node at the Head in a Doubly Linked List
Isomorphic Strings
Binary Representation
Recursive String Permutation
Bubble Sort
Replace all Spaces
Merge Two Sorted Arrays
Remove Duplicate Nodes
Matrix Max Sum Path with Dynamic Programming
Recursively Merge Two Sorted Linked Lists
Bit Conversion
Find the Number that Appears Once
Reverse a Linked List in Pairs
Distance of a node from the root
Largest Square
Mobile Game Range Module - Inserting Ranges
Power of 2
Jam into a BST
Looping Lists : Space complexity O(n)
Convert a Binary Tree to its Mirror Image
Bit Swapping
Introduction to Tries
Image Manipulation
Snake
Word Similarity - Edit Distance
C
Java
Python