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Storage Scalability
Design Cache
Amazon
Facebook
Google
Ola Cabs
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Highly Available Database
Amazon
Facebook
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Sharding a Database
Amazon
Dropbox
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Arrays
Rotate Matrix
Arrangement
Google
Facebook
Amazon
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Find Duplicate in Array
Missing / Repeated number
Bucketing
Bucketing or sorting
Amazon
VMWare
Riverbed
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Spiral Order Matrix I
Simulation array
Microsoft
JP Morgan
Amazon
Flipkart
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Repeat and Missing Number Array
Missing / Repeated number
Array Math
Amazon
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Set Matrix Zeros
Space recycle
Oracle
Amazon
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Spiral Order Matrix II
Simulation array
Microsoft
JP Morgan
Amazon
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Largest Number
Arrangement
Bucketing
Bucketing or sorting
Amazon
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Pascal Triangle
Simulation array
Google
Amazon
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Max Distance
Bucketing
Bucketing or sorting
Google
Amazon
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Next Permutation
Arrangement
Microsoft
Amazon
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System Design Interview Questions
Design URL Shortener
Amazon
Directi
Zenefits
Facebook
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Design Messenger
Amazon
Amazon Lab126
Facebook
Google
Twitter
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Math
Excel Column Number
Base conversion
Amazon
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Excel Column Title
Base conversion
Amazon
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Grid Unique Paths
Combinatorics
Google
Amazon
Microsoft
Adobe
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Power Of Two Integers
Adhoc
Housing
Amazon
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Binary Search
Median of Array
Sort modification
Amazon
VMWare
Google
Microsoft
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Square Root of Integer
Search answer
Facebook
Amazon
Microsoft
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Strings
Implement StrStr
String Search
Facebook
Amazon
Qualcomm
Wipro
Microsoft
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Integer To Roman
String math
Amazon
Facebook
Microsoft
Twitter
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Roman To Integer
String math
Amazon
Facebook
Microsoft
Twitter
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Length of Last Word
Words
Amazon
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Atoi
String parsing
Adobe
Nvidia
Agilent systems
Bloomberg
Amazon
Apple
Microsoft
Groupon
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Valid Ip Addresses
String parsing
Amazon
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Compare Version Numbers
String parsing
Intuit
Amazon
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Longest Palindromic Substring
string Tricks
Amazon
Microsoft
Groupon
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Reverse the String
Words
Qualcomm
Amazon
Microsoft
Cisco
Facebook
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Power of 2
String math
Amazon
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Bit Manipulation
Reverse Bits
Bit play
Nvidia
HCL
Amazon
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Single Number
Bit array
Amazon
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Divide Integers
Bit play
Microsoft
Amazon
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Single Number II
Bit array
Google
Amazon
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Two Pointers
3 Sum
Sorting
Facebook
Amazon
Microsoft
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Remove Duplicates from Sorted Array
Inplace Update
United Healthgroup
Amazon
Google
Microsoft
Expedia
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Remove Element from Array
Inplace Update
Amazon
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Linked Lists
Rotate List
List 2 pointer
Amazon
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Reorder List
List 2 pointer
pointer move
list trick
Amazon
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Add Two Numbers as Lists
List math
Amazon
Qualcomm
Microsoft
Facebook
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Remove Nth Node from List End
List 2 pointer
HCL
Amazon
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List Cycle
List math
List cycle
Amazon
Microsoft
NetApp
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Intersection of Linked Lists
List 2 pointer
Amazon
Microsoft
NetApp
Apache Design
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Reverse Link List II
List 2 pointer
pointer move
list trick
Facebook
Microsoft
Amazon
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Palindrome List
List 2 pointer
Amazon
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Stacks And Queues
Rain Water Trapped
Stack math
Qualcomm
Amazon
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Generate all Parentheses
Stack simple
Amazon
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Min Stack
Multiple stack
Yahoo
Amazon
Adobe
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Redundant Braces
Stack simple
Amazon
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Nearest Smaller Element
cleverstack
Amazon
Microsoft
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Backtracking
Kth Permutation Sequence
Maths and backtracking
Amazon
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Combination Sum
Subsets
Facebook
Amazon
Adobe
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Combination Sum II
Subsets
Microsoft
Amazon
Infosys
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NQueens
Game solving
Pruned builder
Qualcomm
Google
Amazon
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Combinations
Subsets
Amazon
Adobe
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Subsets II
Subsets
Amazon
Microsoft
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Subset
Subsets
Amazon
Microsoft
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Palindrome Partitioning
Bruteforce builder
Pruned builder
Amazon
Google
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Hashing
Longest Consecutive Sequence
Amazon
Google
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4 Sum
Hash Search
Amazon
Google
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Anagrams
Key formation
Amazon
Microsoft
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Fraction
Maths and hashing
Amazon
Microsoft
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Points on the Straight Line
Maths and hashing
Google
Amazon
InMobi
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2 Sum
Hash Search
Facebook
Amazon
Google
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Valid Sudoku
Hash Search
Google
Amazon
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Copy List
Key formation
Amazon
Microsoft
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Longest Substring Without Repeat
Hashing two pointer
Amazon
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Heaps And Maps
Merge K Sorted Lists
heap
Flipkart
Amazon
Google
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LRU Cache
heapmap
Adobe
Citigroup
Amazon
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Distinct Numbers in Window
heapmap
Amazon
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Trees
Inorder Traversal
Traversal
Amazon
Microsoft
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Inorder Traversal of Cartesian Tree
Tree construction
Amazon
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Least Common Ancestor
Tree search
Facebook
Adobe
Microsoft
Amazon
Google
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Construct Binary Tree From Inorder And Preorder
Tree construction
Amazon
Microsoft
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Flatten Binary Tree to Linked List
LinkedList tree
Adobe
Amazon
Microsoft
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Valid Binary Search Tree
Simple tree ops
Amazon
Facebook
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Preorder Traversal
Traversal
Amazon
Microsoft
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Binary Tree From Inorder And Postorder
Tree construction
Amazon
Microsoft
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Balanced Binary Tree
Simple tree ops
Amazon
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Sorted Array To Balanced BST
Tree construction
VMWare
Amazon
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Symmetric Binary Tree
2 trees
Amazon
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Postorder Traversal
Traversal
Amazon
Microsoft
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Populate Next Right Pointers Tree
level order
Microsoft
Amazon
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Identical Binary Trees
2 trees
Amazon
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BST Iterator
BST traversal
Apple
Amazon
Facebook
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ZigZag Level Order Traversal BT
level order
Amazon
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Path Sum
Root to leaf
Microsoft
Yahoo
Amazon
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Next Pointer Binary Tree
Microsoft
Amazon
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Min Depth of Binary Tree
Root to leaf
Facebook
Amazon
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Root to Leaf Paths With Sum
Root to leaf
Microsoft
Yahoo
Amazon
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Kth Smallest Element In Tree
BST traversal
Amazon
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2-Sum Binary Tree
BST traversal
Amazon
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Vertical Order traversal of Binary Tree
Traversal
Amazon
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Dynamic Programming
Longest Increasing Subsequence
2D string DP
Facebook
Yahoo
Epic systems
Amazon
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Unique Binary Search Trees
DP optimized backtrack
Amazon
Twitter
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Max Product Subarray
Suffix / prefix DP
Amazon
LinkedIn
Microsoft
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Ways to Decode
Simple array DP
Facebook
Amazon
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Best Time to Buy and Sell Stocks II
Adhoc
Amazon
Facebook
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Best Time to Buy and Sell Stocks III
DP tricky
Amazon
Facebook
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Best Time to Buy and Sell Stocks I
Suffix / prefix DP
Amazon
Facebook
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Max Sum Path in Binary Tree
tree DP
Directi
Amazon
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Palindrome Partitioning II
Breaking words
Amazon
Google
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Min Sum Path in Matrix
Matrix DP
Amazon
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Min Jumps Array
Greedy OR DP
Amazon
Ebay
Google
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Unique Binary Search Trees II
Multiply DP
Amazon
Twitter
Samsung
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Jump Game Array
Greedy OR DP
Amazon
Ebay
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Stairs
Simple array DP
Morgan Stanley
Amazon
Intel
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Evaluate Expression To True
DP tricky
Amazon
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Arrange II
Suffix / prefix DP
Amazon
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Equal Average Partition
Knapsack
Amazon
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Greedy Algorithm
Gas Station
Bucket 2
Bloomberg
Google
DE Shaw
Amazon
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Highest Product
Bucket 5
Coursera
Amazon
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Assign Mice to Holes
Bucket 1
Amazon
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Graph Data Structure & Algorithms
Clone Graph
graph hashing
Google
Facebook
Amazon
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Word Search Board
graph traversal
Epic systems
Amazon
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Black Shapes
graph connectivity
Amazon
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Knight On Chess Board
Shortest path
Goldman Sachs
Amazon
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Smallest Multiple With 0 and 1
BFS
Amazon
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Commutable Islands
graph connectivity
Amazon
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Possibility of finishing all courses given pre-requisites
graph connectivity
Amazon
Depth first search
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Valid Path
BFS
graph connectivity
Morgan Stanley
Amazon
Codenation
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Puzzles
Monkeys and Doors
Math
Amazon
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The Tribe
Logical deduction
Amazon
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Prisoners and Poison
Math
Amazon
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Light Switches in the Cellar
Game
Amazon
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Next Number II
Math
Amazon
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