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