Categories of Questions

## Flipkart Array Questions

**Question 1. Minimum operation to make all elements equal in array** The problem “Minimum operation to make all elements equal in array” states that you are given an array with some integers in it. You have to find out the minimum operations that can be done to make an array equal. Example [ 1,3,2,4,1] 3 Explanation Either 3 subtractions can be ...

**Question 2. Count number of triplets with product equal to given number** The problem “Count number of triplets with product equal to given number” states that we are given an integer array and a number m. The problem statement asks to find out the total number of triplets of with product equals to m. Example arr[] = {1,5,2,6,10,3} m=30 3 Explanation Triplets ...

**Question 3. Find Index of Closing Bracket for a Given Opening Bracket in an Expression** Problem Statement Given a string s of length/size n and an integer value representing the index of an opening square bracket. Find index of closing bracket for a given opening bracket in an expression. Example s = "[ABC[23]][89]" index = 0 8 s = "[C-[D]]" index = 3 5 s ...

**Question 4. Gold Mine Problem** Problem Statement The “Gold Mine problem” states that you are given a 2D grid having some non-negative coins placed in each cell of the given grid. Initially, the miner is standing at the first column but there is no restriction on the row. He can start in any row. The ...

**Question 5. Largest Sum Contiguous Subarray** Problem Statement You are given an array of integers. The problem statement asks to find out the largest sum contiguous subarray. This means nothing but to find a subarray (continuous elements) which has the largest sum among all other subarrays in the given array. Example arr[] = {1, -3, 4, ...

**Question 6. Find Maximum of Minimum for Every Window Size in a Given Array** Given an array a[ ] of size n. For every window size that varies from 1 to n in array print or find maximum of minimum for every window size in a given array. Example Input : a[ ] = {10, 20, 30, 50, 10, 70, 30} Output : 70 30 20 ...

**Question 7. Trapping Rain Water LeetCode Solution** In the Trapping Rain Water LeetCode problem, we have given N non-negative integers representing an elevation map and the width of each bar is 1. We have to find the amount of water that can be trapped in the above structure. Example Let’s understand that by an example For the ...

**Question 8. Container with Most Water** Problem description : you are given n integers (y0, y1, y2 … yn-1) at n indices (i = 0,1,2 … n-1). Integer at i-th index is yi. Now, you draw n lines on a cartesian plane each connecting points (i, yi) and (i, 0). Find the maximum volume of water ...

**Question 9. The Celebrity Problem** Problem Statement In the celebrity problem there is a room of N people, Find the celebrity. Conditions for Celebrity is- If A is Celebrity then Everyone else in the room should know A. A shouldn’t know anyone in the room. We need to find the person who satisfies these conditions. ...

**Question 10. Count Number of Occurrences in a Sorted Array** Problem Statement In the “Count Number of Occurrences in a Sorted Array” problem, we have given a sorted array. Count the number of occurrences or frequency in a sorted array of X where X is an integer. Example Input 13 1 2 2 2 2 3 3 3 4 4 ...

## Flipkart String Questions

**Question 11. Check for Palindrome after every character replacement Query** The problem “Check for Palindrome after every character replacement Query” states that suppose you are given a String and no. of Queries, each query has two integer input values as i1 and i2 and one character input called ‘ch’. The problem statement asks to change the values at i1 and ...

**Question 12. Find Index of Closing Bracket for a Given Opening Bracket in an Expression** Problem Statement Given a string s of length/size n and an integer value representing the index of an opening square bracket. Find index of closing bracket for a given opening bracket in an expression. Example s = "[ABC[23]][89]" index = 0 8 s = "[C-[D]]" index = 3 5 s ...

**Question 13. Queue based approach for first non-repeating character in a stream** Problem Statement The problem “Queue based approach for first non-repeating character in a stream” states that you are given a stream containing lower case characters, find the first non-repeating character whenever a new character is added to the stream, and if there is no non-repeating character return -1. Examples aabcddbe ...

**Question 14. Next Permutation** In the next permutation problem we have given a word, find the lexicographically greater_permutation of it. Example input : str = "tutorialcup" output : tutorialpcu input : str = "nmhdgfecba" output : nmheabcdfg input : str = "algorithms" output : algorithsm input : str = "spoonfeed" output : Next Permutation ...

**Question 15. Smallest Palindrome after Replacement** Problem Statement In the “Smallest Palindrome after Replacement” problem we have given the input string contains lower case alphabets characters and dots(.). We need to replace all dots with some alphabet character in such a way that the resultant string becomes a palindrome. The palindrome should be lexicographically smallest. Input ...

**Question 16. Smallest window in a string containing all characters of another string** Find the shortest substring in a given string that contains all the characters of a given word or Find the Smallest window in a string containing all characters of another string Given two strings s and t, write a function that will find the minimum window in s which will ...

## Flipkart Tree Questions

**Question 17. Bottom View of a Binary Tree** Problem Statement The problem “Bottom View of a Binary Tree” states that you are given a binary tree and now you need to find the bottom view for the given tree. When we see a tree from the downward direction. The nodes which are visible to us is the bottom ...

**Question 18. Level order Traversal in Spiral Form** In this problem we have given a binary tree, print its level order traversal in a spiral form. Examples Input Output 10 30 20 40 50 80 70 60 Naive Approach for Level order Traversal in Spiral Form The idea is to do a normal level order traversal using a ...

**Question 19. Print a Binary Tree in Vertical Order** In this problem, we have given a pointer denoting the root of the binary tree and your task is to print the binary tree in the vertical order. Example Input 1 / \ 2 3 / \ / \ 4 5 6 7 \ \ 8 9 Output 4 2 ...

**Question 20. Binary Tree zigzag level order Traversal** Given a binary tree, print the zigzag level order traversal of its node values. (ie, from left to right, then right to left for the next level and alternate between). Example consider the binary tree given below Below is the zigzag level order traversal of the above binary tree Types ...

## Flipkart Graph Questions

**Question 21. Topological Sorting** Given a directed acyclic graph, topologically sort the graph nodes. Topological Sorting Example Topological sorting of above graph is -> {1,2,3,0,5,4} Theory Topological Sorting is done for a Directed Acyclic Graph (DAG). A DAG has no cycles in it. ie, there is no such path starting from any node of ...

## Flipkart Stack Questions

**Question 22. Find Index of Closing Bracket for a Given Opening Bracket in an Expression** Problem Statement Given a string s of length/size n and an integer value representing the index of an opening square bracket. Find index of closing bracket for a given opening bracket in an expression. Example s = "[ABC[23]][89]" index = 0 8 s = "[C-[D]]" index = 3 5 s ...

**Question 23. Design a stack that supports getMin() in O(1) time and O(1) extra space** Design a stack that supports getMin() in O(1) time and O(1) extra space. Thus the special stack data structure must support all the operations of the stack like – void push() int pop() bool isFull() bool isEmpty() in constant time. Add an additional operation getMin() to return the minimum value ...

**Question 24. Find Maximum of Minimum for Every Window Size in a Given Array** Given an array a[ ] of size n. For every window size that varies from 1 to n in array print or find maximum of minimum for every window size in a given array. Example Input : a[ ] = {10, 20, 30, 50, 10, 70, 30} Output : 70 30 20 ...

**Question 25. Level order Traversal in Spiral Form** In this problem we have given a binary tree, print its level order traversal in a spiral form. Examples Input Output 10 30 20 40 50 80 70 60 Naive Approach for Level order Traversal in Spiral Form The idea is to do a normal level order traversal using a ...

**Question 26. Queue using Stacks** In queue using a stack problem, we have to implement the following functions of a queue using the standard functions of stack data structure, Enqueue: Add an element to the end of the queue Dequeue: Remove an element from the start of the queue Example Input: Enqueue(5) Enqueue(11) Enqueue(39) Dequeue() ...

**Question 27. Trapping Rain Water LeetCode Solution** In the Trapping Rain Water LeetCode problem, we have given N non-negative integers representing an elevation map and the width of each bar is 1. We have to find the amount of water that can be trapped in the above structure. Example Let’s understand that by an example For the ...

**Question 28. Binary Tree zigzag level order Traversal** Given a binary tree, print the zigzag level order traversal of its node values. (ie, from left to right, then right to left for the next level and alternate between). Example consider the binary tree given below Below is the zigzag level order traversal of the above binary tree Types ...

**Question 29. The Celebrity Problem** Problem Statement In the celebrity problem there is a room of N people, Find the celebrity. Conditions for Celebrity is- If A is Celebrity then Everyone else in the room should know A. A shouldn’t know anyone in the room. We need to find the person who satisfies these conditions. ...

## Flipkart Queue Questions

**Question 30. Queue based approach for first non-repeating character in a stream** Problem Statement The problem “Queue based approach for first non-repeating character in a stream” states that you are given a stream containing lower case characters, find the first non-repeating character whenever a new character is added to the stream, and if there is no non-repeating character return -1. Examples aabcddbe ...

**Question 31. Queue using Stacks** In queue using a stack problem, we have to implement the following functions of a queue using the standard functions of stack data structure, Enqueue: Add an element to the end of the queue Dequeue: Remove an element from the start of the queue Example Input: Enqueue(5) Enqueue(11) Enqueue(39) Dequeue() ...

**Question 32. Binary Tree zigzag level order Traversal** Given a binary tree, print the zigzag level order traversal of its node values. (ie, from left to right, then right to left for the next level and alternate between). Example consider the binary tree given below Below is the zigzag level order traversal of the above binary tree Types ...

## Flipkart Matrix Questions

**Question 33. Gold Mine Problem** Problem Statement The “Gold Mine problem” states that you are given a 2D grid having some non-negative coins placed in each cell of the given grid. Initially, the miner is standing at the first column but there is no restriction on the row. He can start in any row. The ...

**Question 34. The Celebrity Problem** Problem Statement In the celebrity problem there is a room of N people, Find the celebrity. Conditions for Celebrity is- If A is Celebrity then Everyone else in the room should know A. A shouldn’t know anyone in the room. We need to find the person who satisfies these conditions. ...

## Flipkart Other Questions

**Question 35. Union and Intersection of two Linked Lists** Given two linked lists, create another two linked lists to get union and intersection of the elements of existing lists. Example Input: List1: 5 → 9 → 10 → 12 → 14 List2: 3 → 5 → 9 → 14 → 21 Output: Intersection_list: 14 → 9 → 5 Union_list: ...

**Question 36. Cutting a Rod** Problem Statement The problem “Cutting a Rod” states that you are given a rod of some particular length and prices for all sizes of rods which are smaller than or equal to the input length. That is we know the price for rods of length from 1 to n, considering ...

**Question 37. Cuckoo sequence program** Problem Statment Cuckoo sequence program or Cuckoo Hashing is a method used to solve the problem when a collision occurs in a Hash Table. Collisions are likely of two hash values of a hash function in a table. A collision occurs when two hash values for the same key occurs ...