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List of Interview Questions and Answers

• Combinations and Permutations

• Find the Maximum BST Node

• Binary Search on Array of Integers

• Find the N^th Node from the end without using extra memory - Linked List

• Fibonacci Number

• Count the Leaves!

• Find the Middle of a List in a Single Pass

• Remove Duplicates from a List of Words

• Power of 2

• Even or Odd?

• Replace all Spaces

• Find the Lowest Common Ancestor of Two Tree Nodes

• Subset Summation with Number Constraint

• Number of Full Nodes in a Binary Tree

• Matrix Max Sum Path with Dynamic Programming

• Find the Level that has the Maximum Sum

• Snake

• Insert Stars

• The Deepest Node

• Find a Node in a Binary Tree Without Using Recursion

• Find the Maximum Number of Repetitions

• Print a Binary Tree Level by Level

• Merge Two Sorted Arrays

• Is this Integer a Palindrome?

• Find the Transpose of a Square Matrix

• Better Fibonacci

• Print all Possible Characters

• Stock Market Oracle

• Even Split

• Happy Numbers!

• Boggle Search

• Boggle with Paper Dictionary

• Rotate a Square Image Counterclockwise

• Check Balanced Parentheses

• Minimum Depth of a Tree

• Flip it!

• Delete a List's Tail Node

• Introduction to Tries

• Horizontal Flip

• Find the First Non Duplicate Character in a String

• 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

• Insert a Node at the Head of a Circular Linked List

• Number of Half Nodes in a Binary Tree

• BST Validation

• 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

• Minimum Sum Path in a Triangle

• Insert a Node at the Front of a Linked List

• Making Change

• Insert a Node at the End of a Linked List

• 1-800-PROBLEM

• Recursive Inorder Traversal

• Pascal's Triangle

• Recursive Postorder Traversal

• Couple Sum

• Are these Binary Trees Identical?

• Iterative Postorder Traversal

• Delete the Head Node of a Circular Linked List

• Find the Sum of all Elements in a Binary Tree

• Repeated Elements in an Array

• Roll the Dice!

• Parse Simple Mathematical Expressions

• Natural Language Parser

• Does an Element N Exist in a Given Binary Tree?

• Permutations!

• Palindrome Tester

• Matrix Max Sum Path with DFS

• Find the size of the Binary Tree

• Reverse a Linked List in Pairs

• Iterative Inorder Traversal

• Check a Linked List for Loops or Cycles With O(1) Space Complexity

• Find the N^th Node from the End - Linked List

• Bit Conversion

• Selection Sort

• Largest Square

• Recursively Merge Two Sorted Linked Lists

• Is this List a Palindrome?

• Distance between two nodes in a Binary Tree

• Image Manipulation

• Rotate Linear Array

• Rotate a Square Image Clockwise

• Mirror Mirror on the Wall ...

• Insert a Node at the Specified Position in Doubly Linked List

• Recursive String Permutation

• Graph Depth First Search

• Find the Missing Number in a Set of Numbers from 1 to 10

• Delete a List's Head Node

• Unique Chars in a String

• Subset Summation

• Fill in the Ancestors of the Node in a Binary Tree

• Anagrams

• Reverse an Integer

• Find a BST Node

• Binary Representation

• Delete a Circular-Linked List's Tail Node

• Find the Number that Appears Once

• Isomorphic Strings

• Add Two Linked List-ish Numbers

• Delete the Node at a Particular Position in a Linked List

• Remove Duplicate Nodes

• Distance of a node from the root

• Find the Minimum BST Node

• Find the Sum of all Elements in a Binary Tree Iteratively

• Steal the Node

• Minimum Sum Path

• Generate Combinations of Parentheses

• String Compression

• Implement the Djikstra Shortest Path Algorithm in a Graph

• 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

• Bubble Sort

• Delete the Node at the Specific Position in a Doubly Linked List

• Full Tree Decompression

• Implement the Breadth First Search Algorithm for a Graph

• Jam into a BST

• Print all Nodes in the Range a .. b in a given BST

• Find the Max Element in a Binary Tree Recursively

• Print Paths

• Find the Maximum Contiguous Subsequence in an Array

• Mobile Game Range Module - Merging Ranges

• Looping Lists : Space complexity O(n)

• Insert a Node at a specified position in a Linked List

• Levelorder Traversal

• Reverse a Singly Linked List

• Recursive Preorder Traversal

• Reverse Level Order Traversal

• Find the k^th Largest Node in a BST

• Insert a Node at the Tail of a Circular Linked List

• Iteratively, find the Max Element in a Give Binary Tree

• Count Paths on a Game Board

• POW!

• Height of a Binary Tree

• Bit Swapping

• 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 1s 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