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