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