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