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