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Online AssessmentDSA / CodingMachine CodingLow-Level Design

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Online AssessmentDSA / CodingMachine CodingLow-Level DesignSystem DesignTech Deep-DiveHiring ManagerBehavioral / HR

Round 02 · 60 questions

DSA / Coding

Data structures & algorithms on a whiteboard or shared editor.

  • 1Password
    Jump game.
    FrontendNew Grad / JuniorMedium◆ Commonly asked
    #greedy#dp
    PracticeLeetCode↗GeeksforGeeks↗
  • 1Password
    Permutations.
    FrontendNew Grad / JuniorMedium◆ Commonly asked
    #backtracking
    PracticeLeetCode↗GeeksforGeeks↗
  • 1Password
    Valid Parentheses — check balanced brackets.
    FrontendNew Grad / JuniorEasy◆ Commonly asked
    #stack#string
    PracticeLeetCode↗GeeksforGeeks↗
  • 1Password
    Set matrix zeroes.
    BackendMidMedium◆ Commonly asked
    #matrix
    PracticeLeetCode↗GeeksforGeeks↗
  • 1Password
    Group anagrams from a list of strings.
    BackendMidMedium◆ Commonly asked
    #hashmap#string
    PracticeLeetCode↗GeeksforGeeks↗
  • 1Password
    Longest consecutive sequence.
    BackendMidMedium◆ Commonly asked
    #hashmap#array
    PracticeLeetCode↗GeeksforGeeks↗
  • 1Password
    Find minimum in rotated sorted array.
    Full-stackSeniorMedium◆ Commonly asked
    #binary-search
    PracticeLeetCode↗GeeksforGeeks↗
  • 1Password
    3Sum.
    Full-stackSeniorMedium◆ Commonly asked
    #two-pointers#array
    PracticeLeetCode↗GeeksforGeeks↗
  • 1Password
    Two Sum — return indices of numbers adding to a target.
    Full-stackSeniorEasy◆ Commonly asked
    #array#hashmap
    PracticeLeetCode↗GeeksforGeeks↗
  • 1Password
    Clone a graph.
    FrontendSeniorMedium◆ Commonly asked
    #graph#dfs
    PracticeLeetCode↗GeeksforGeeks↗
  • 1Password
    Sort colors.
    FrontendSeniorMedium◆ Commonly asked
    #two-pointers#array
    PracticeLeetCode↗GeeksforGeeks↗
  • 1Password
    Container with most water.
    FrontendSeniorMedium◆ Commonly asked
    #two-pointers#array
    PracticeLeetCode↗GeeksforGeeks↗
  • 1Password
    Longest palindromic substring.
    BackendStaff+Medium◆ Commonly asked
    #string#dp
    PracticeLeetCode↗GeeksforGeeks↗
  • 1Password
    Best time to buy and sell stock.
    BackendStaff+Easy◆ Commonly asked
    #array#greedy
    PracticeLeetCode↗GeeksforGeeks↗
  • 1Password
    Climbing stairs.
    BackendStaff+Easy◆ Commonly asked
    #dp
    PracticeLeetCode↗GeeksforGeeks↗
  • Abridge
    Search in a rotated sorted array.
    Full-stackMidMedium◆ Commonly asked
    #binary-search
    PracticeLeetCode↗GeeksforGeeks↗
  • Abridge
    Word ladder — shortest transformation sequence.
    Full-stackMidHard◆ Commonly asked
    #bfs#graph
    PracticeLeetCode↗GeeksforGeeks↗
  • Abridge
    Edit distance.
    Full-stackMidHard◆ Commonly asked
    #dp#string
    PracticeLeetCode↗GeeksforGeeks↗
  • Abridge
    Merge two sorted linked lists.
    BackendNew Grad / JuniorEasy◆ Commonly asked
    #linked-list
    PracticeLeetCode↗GeeksforGeeks↗
  • Abridge
    Merge intervals.
    BackendNew Grad / JuniorMedium◆ Commonly asked
    #intervals#sorting
    PracticeLeetCode↗GeeksforGeeks↗
  • Abridge
    Valid Parentheses — check balanced brackets.
    BackendNew Grad / JuniorEasy◆ Commonly asked
    #stack#string
    PracticeLeetCode↗GeeksforGeeks↗
  • Abridge
    Container with most water.
    FrontendStaff+Medium◆ Commonly asked
    #two-pointers#array
    PracticeLeetCode↗GeeksforGeeks↗
  • Abridge
    House robber.
    FrontendStaff+Medium◆ Commonly asked
    #dp
    PracticeLeetCode↗GeeksforGeeks↗
  • Abridge
    Subsets.
    FrontendStaff+Medium◆ Commonly asked
    #backtracking
    PracticeLeetCode↗GeeksforGeeks↗
  • Abridge
    Subtree of another tree.
    Full-stackStaff+Easy◆ Commonly asked
    #tree#dfs
    PracticeLeetCode↗GeeksforGeeks↗
  • Abridge
    Min cost to connect all points.
    Full-stackStaff+Medium◆ Commonly asked
    #graph#mst
    PracticeLeetCode↗GeeksforGeeks↗
  • Abridge
    Sliding window maximum.
    Full-stackStaff+Hard◆ Commonly asked
    #deque#sliding-window
    PracticeLeetCode↗GeeksforGeeks↗
  • Abridge
    Implement a trie (prefix tree).
    FrontendNew Grad / JuniorMedium◆ Commonly asked
    #trie
    PracticeLeetCode↗GeeksforGeeks↗
  • Abridge
    Kth smallest element in a BST.
    FrontendNew Grad / JuniorMedium◆ Commonly asked
    #tree#bst
    PracticeLeetCode↗GeeksforGeeks↗
  • Abridge
    Word break.
    FrontendNew Grad / JuniorMedium◆ Commonly asked
    #dp#string
    PracticeLeetCode↗GeeksforGeeks↗
  • Accenture
    Matrix operations: transpose and sum of the diagonals.
    Full-stackInternMedium◆ Commonly asked
    #matrix
    PracticeGeeksforGeeks↗Search↗
  • Accenture
    Implement binary search on a sorted array.
    Full-stackInternEasy◆ Commonly asked
    #searching
    PracticeGeeksforGeeks↗Search↗
  • Accenture
    Count the frequency of each character in a string.
    BackendSeniorEasy◆ Commonly asked
    #string
    PracticeGeeksforGeeks↗Search↗
  • Accenture
    Count vowels, consonants and words in a string.
    BackendSeniorEasy◆ Commonly asked
    #string
    PracticeGeeksforGeeks↗Search↗
  • Accenture
    Sort an array using bubble sort and state its complexity.
    BackendNew Grad / JuniorEasy◆ Commonly asked
    #sorting
    PracticeGeeksforGeeks↗Search↗
  • Accenture
    Find the sum of digits of a number.
    BackendNew Grad / JuniorEasy◆ Commonly asked
    #math
    PracticeGeeksforGeeks↗Search↗
  • Accenture
    Print a star / pyramid pattern for n rows.
    Full-stackNew Grad / JuniorEasy◆ Commonly asked
    #patterns
    PracticeGeeksforGeeks↗Search↗
  • Accenture
    Remove duplicate characters from a string.
    Full-stackNew Grad / JuniorEasy◆ Commonly asked
    #string
    PracticeGeeksforGeeks↗Search↗
  • Accenture
    Check whether a number is an Armstrong number.
    BackendInternEasy◆ Commonly asked
    #math
    PracticeGeeksforGeeks↗Search↗
  • Accenture
    Remove duplicates from an array without using extra space.
    BackendInternMedium◆ Commonly asked
    #array
    PracticeGeeksforGeeks↗Search↗
  • Acko
    Insert interval.
    BackendSeniorMedium◆ Commonly asked
    #intervals
    PracticeLeetCode↗GeeksforGeeks↗
  • Acko
    Jump game.
    BackendSeniorMedium◆ Commonly asked
    #greedy#dp
    PracticeLeetCode↗GeeksforGeeks↗
  • Acko
    Word search II.
    BackendSeniorHard◆ Commonly asked
    #trie#backtracking
    PracticeLeetCode↗GeeksforGeeks↗
  • Acko
    Median of two sorted arrays.
    FrontendMidHard◆ Commonly asked
    #binary-search
    PracticeLeetCode↗GeeksforGeeks↗
  • Acko
    Two Sum — return indices of numbers adding to a target.
    FrontendMidEasy◆ Commonly asked
    #array#hashmap
    PracticeLeetCode↗GeeksforGeeks↗
  • Acko
    Regular expression matching.
    FrontendMidHard◆ Commonly asked
    #dp#string
    PracticeLeetCode↗GeeksforGeeks↗
  • Acko
    Valid Parentheses — check balanced brackets.
    Full-stackMidEasy◆ Commonly asked
    #stack#string
    PracticeLeetCode↗GeeksforGeeks↗
  • Acko
    Word search in a grid.
    Full-stackMidMedium◆ Commonly asked
    #backtracking#grid
    PracticeLeetCode↗GeeksforGeeks↗
  • Acko
    Edit distance.
    Full-stackMidHard◆ Commonly asked
    #dp#string
    PracticeLeetCode↗GeeksforGeeks↗
  • Acko
    Maximum depth of a binary tree.
    BackendNew Grad / JuniorEasy◆ Commonly asked
    #tree#dfs
    PracticeLeetCode↗GeeksforGeeks↗
  • Acko
    Best time to buy and sell stock.
    BackendNew Grad / JuniorEasy◆ Commonly asked
    #array#greedy
    PracticeLeetCode↗GeeksforGeeks↗
  • Acko
    Valid anagram.
    BackendNew Grad / JuniorEasy◆ Commonly asked
    #string#hashmap
    PracticeLeetCode↗GeeksforGeeks↗
  • Acko
    Coin change — fewest coins to make an amount.
    FrontendStaff+Medium◆ Commonly asked
    #dp
    PracticeLeetCode↗GeeksforGeeks↗
  • Acko
    Lowest common ancestor of a binary tree.
    FrontendStaff+Medium◆ Commonly asked
    #tree
    PracticeLeetCode↗GeeksforGeeks↗
  • Acko
    Group anagrams from a list of strings.
    FrontendStaff+Medium◆ Commonly asked
    #hashmap#string
    PracticeLeetCode↗GeeksforGeeks↗
  • Activision Blizzard
    Diameter of a binary tree.
    Full-stackNew Grad / JuniorEasy◆ Commonly asked
    #tree#dfs
    PracticeLeetCode↗GeeksforGeeks↗
  • Activision Blizzard
    Valid anagram.
    Full-stackNew Grad / JuniorEasy◆ Commonly asked
    #string#hashmap
    PracticeLeetCode↗GeeksforGeeks↗
  • Activision Blizzard
    Reverse nodes in k-group.
    Full-stackNew Grad / JuniorHard◆ Commonly asked
    #linked-list
    PracticeLeetCode↗GeeksforGeeks↗
  • Activision Blizzard
    Product of array except self.
    BackendSeniorMedium◆ Commonly asked
    #array#prefix-sum
    PracticeLeetCode↗GeeksforGeeks↗
  • Activision Blizzard
    LRU cache with O(1) get and put.
    BackendSeniorMedium◆ Commonly asked
    #hashmap#linked-list
    PracticeLeetCode↗GeeksforGeeks↗

More practice · open source

Topic banks

59extra questions on this round's topics, imported from MIT-licensed open-source repositories. These are topic questions — they are not attributed to any company.

Data Structures31 questions›
  • ·What is data-structure?
  • ·What is a graph?
  • ·What is linear searching?
  • ·What is algorithm?
  • ·What is linear data structure and what are common operations to perform on it?
  • ·What is an average case complexity of Bubble Sort?
  • ·What examples of greedy algorithms do you know?
  • ·What are some examples of divide and conquer algorithms?
  • ·What are some examples of dynamic programming algorithms?
  • ·Why do we use stacks?
  • ·Why do we use queues?
  • ·What is Selection Sort?
  • ·Why we need to do algorithm analysis?
  • ·What is the difference between Linear Search and Binary Search?
  • ·What is asymptotic analysis of an algorithm?
  • ·Name some approaches to develop algorithms
  • ·What is Circular Queue and why will you use one?
  • ·Why is Insertion sort better than Quick sort for small list of elements?
  • ·Tell me something about Insertion sort?
  • ·List some advantages of Insertion Sort
  • ·How Insertion sort and Selection sorts are different?
  • ·What is Merge Sort and how it works?
  • ·How Quick Sort works?
  • ·What is Shell Sort?
  • ·Is there ever a good reason to use Insertion Sort?
  • ·Is there any advantages of Bubble Sort?
  • ·What is Bucket Sort?
  • ·What is Tim Sort and how would you compare it with Quick Sort?
  • ·Why is Quick Sort better than Merge Sort?
  • ·What is stability in sorting algorithms and why is it important?
  • ·[↑] Back to top
⎇ FAQGURU/FAQGURU · MIT ↗
Code Problems28 questions›
  • ·Test divisors of three
  • ·Sum of Array Plus One
  • ·String Rotation
  • ·Oddball sum
  • ·Simple clock angle
  • ·Sum of several arrays
  • ·Lucky sevens
  • ·Two sum problem
  • ·Implement a queue using a linked list
  • ·Tree Level Order Print
  • ·Stock maximum profit
  • ·Find Word Positions in Text
  • ·Determine overlapping numbers in ranges
  • ·Throttle Function Implementation
  • ·Dutch national flag sorting problem
  • ·Step-by-step solution for step counting using recursion
  • ·Implement Bubble Sort
  • ·Implement a queue using two stacks
  • ·Implement pow(a,b) without multiplication or division
  • ·Generate all balanced bracket combinations
  • ·All Permutations (Anagrams) of a String
  • ·Merge two sorted linked lists
  • ·Insert an interval into a list of sorted disjoint intervals
  • ·Find all string combinations consisting only of 0, 1 and ?
  • ·Quickly calculate the cube root of 6 digit numbers
  • ·Transform Word
  • ·Find the missing value in a set of number from 1 to n
  • ·[↑] Back to top
⎇ FAQGURU/FAQGURU · MIT ↗