200+ Member Technical Staff Interview Questions and Answers

Find the next smallest palindrome greater than a given number represented as a string.

• Iterate from the middle of the number and mirror the left side to the right side to create a palindrome

• If the resulting palindrome is greater than the input number, return it

• Handle cases where the number has all 9s and requires a carry over to the left side

The task is to determine the maximum profit that can be achieved by performing up to two buy-and-sell transactions on a given set of stock prices.

• Iterate through the array of stock prices to find the maximum profit that can be achieved by buying and selling stocks at different points.

• Keep track of the maximum profit that can be achieved by considering all possible combinations of buy and sell transactions.

• Ensure that you sell the stock before buying again to adhere to the con...read more

Check if two strings are anagrams of each other by comparing their characters.

• Create a character frequency map for both strings and compare them.

• Sort both strings and compare if they are equal.

• Use a hash set to store characters from one string and remove them while iterating through the other string.

• Check if the character counts of both strings are equal.

• Example: For input 'listen' and 'silent', the output should be true.

The problem involves finding the optimal strategy to accumulate the maximum amount in a coin game with specific rules.

• Start by considering the base cases where there are only 1 or 2 coins.

• Use dynamic programming to keep track of the maximum amount that can be won at each step.

• Consider the different scenarios when choosing a coin from either end of the line.

• Keep track of the total winnings for both players and choose the optimal strategy to maximize your winnings.

• Implement a r...read more

The task is to return the spiral path of elements in a given matrix.

• Iterate through the matrix in a spiral path by keeping track of boundaries.

• Print elements in the order of top row, right column, bottom row, and left column.

• Continue the spiral path until all elements are printed.

Detect if a singly linked list forms a cycle by checking if a node's next pointer points back to a previous node.

• Traverse the linked list using two pointers, one moving one step at a time and the other moving two steps at a time.

• If the two pointers meet at any point, there is a cycle in the linked list.

• Use Floyd's Cycle Detection Algorithm for efficient detection of cycles in linked lists.

Given an array, select elements to maximize sum by removing adjacent elements.

• Iterate through the array and keep track of the count of each element.

• Select the element with the highest count first, then remove adjacent elements.

• Repeat the process until the array is empty and sum the selected elements.

The task is to determine if it is possible to transform a string to match another string using wildcard characters '?' and '*'.

• Iterate through both strings simultaneously, handling wildcard characters '?' and '*' accordingly.

• Use dynamic programming to keep track of matching subproblems.

• Return true if at the end both strings match, false otherwise.

Detect and remove loop in a singly linked list in place with O(n) time complexity and O(1) space complexity.

• Use Floyd's Cycle Detection Algorithm to identify the loop in the linked list.

• Once the loop is detected, use two pointers to find the start of the loop.

• Adjust the pointers to remove the loop and return the modified linked list.

Move all zeroes in an unsorted array to the end while preserving the order of non-zero elements.

• Iterate through the array and maintain two pointers - one for the current position and one for the position to swap with.

• If the current element is non-zero, swap it with the element at the swap pointer and increment the swap pointer.

• After iterating through the array, fill the remaining positions with zeroes.

• Example: Input: [0, 1, -2, 3, 4, 0, 5, -27, 9, 0], Output: [1, -2, 3, 4, 5,...read more

Given an array, find the number of 'good' arrays that can be formed by deleting one element.

• Iterate through each element in the array and check if deleting it results in a 'good' array

• Keep track of the sum of elements at odd and even indices to determine if the array is 'good'

• Return the count of 'good' arrays

The minimum number of swaps required to sort an array of distinct elements in ascending order.

• Use a hashmap to store the index of each element in the array.

• Iterate through the array and swap elements to their correct positions.

• Count the number of swaps needed to sort the array.

Find predecessor and successor of a given node in a binary search tree (BST).

• Predecessor is the node visited just before the given node in an inorder traversal.

• Successor is the node visited immediately after the given node in an inorder traversal.

• Return -1 if predecessor or successor does not exist.

• Implement inorder traversal to find predecessor and successor.

A class in JavaScript is a blueprint for creating objects with similar properties and methods.

• Classes are used to create multiple objects with the same structure and behavior.

• They provide a way to organize and encapsulate related data and functions.

• Classes can have properties (variables) and methods (functions) that define their behavior.

• Instances of a class can be created using the 'new' keyword.

• Classes can also have constructors, which are special methods called when an obj...read more

Find the maximum window size to sort an unsorted array.

• Identify the longest decreasing subarray from the beginning and longest increasing subarray from the end

• Find the minimum and maximum element in the identified subarrays

• Expand the identified subarrays until all elements in the array are covered

• The length of the expanded subarray is the maximum window size

Find the length of the longest common prime subsequence between two arrays of integers.

• Iterate through both arrays to find prime numbers

• Use a set to keep track of common prime numbers

• Return the size of the set as the length of the longest common prime subsequence

Implement a stack using two queues to store integer values with specified functions.

• Create a stack class with two queue data members.

• Implement push(data), pop(), top(), size(), and isEmpty() functions.

• Use one queue for pushing elements and another for temporary storage during operations.

• Ensure proper handling of edge cases such as empty stack.

• Example: If input is Q = 5, 1 42, 2, 3, 1 17, the output should be 42, -1, 17.

Convert the given array into a min-binary heap by modifying the array elements.

• Iterate through the array and heapify each node starting from the last non-leaf node to the root node.

• For each node, compare it with its children and swap if necessary to satisfy the min-heap property.

• Continue this process until the entire array is converted into a min-heap.

Tower of Hanoi problem where 'N' disks need to be moved to another rod following specific rules in less than 2^N moves.

• Implement a recursive function to move disks from one rod to another following the rules.

• Use the concept of recursion and backtracking to solve the Tower of Hanoi problem efficiently.

• Maintain a count of moves and track the movement of disks in a 2-D array/list.

• Ensure that larger disks are not placed on top of smaller disks while moving.

• Return the 2-D array/li...read more

Implement a priority queue using a heap data structure by completing the provided functions.

• Implement push() function to insert elements into the queue.

• Implement pop() function to remove the largest element from the queue.

• Implement getMaxElement() function to return the largest element.

• Implement isEmpty() function to check if the queue is empty.

Implement the merge sort algorithm to sort a given sequence of numbers in non-descending order.

• Divide the input array into two halves recursively until each subarray has only one element.

• Merge the sorted subarrays back together in non-descending order.

• Time complexity of merge sort is O(n log n) and space complexity is O(n).

Yes, I can design the bank architecture using basic OOP concepts in any programming language.

• Create classes for entities like Bank, Account, Customer, Transaction, etc.

• Use inheritance to model relationships between entities (e.g. SavingsAccount and CheckingAccount inheriting from Account).

• Implement encapsulation to hide internal details of classes and provide public interfaces for interaction.

• Utilize polymorphism to allow different classes to be treated as instances of a comm...read more

Merge sort and Quick sort are sorting algorithms used to sort arrays of data.

• Merge sort is a divide and conquer algorithm that divides the input array into two halves, sorts each half recursively, and then merges the sorted halves.

• Quick sort is also a divide and conquer algorithm that selects a pivot element and partitions the array around the pivot, sorting the two resulting sub-arrays recursively.

• Merge sort has a time complexity of O(n log n) and is stable, but requires add...read more

Comparison of heights of two soldiers chosen based on different criteria from a grid of soldiers.

• Soldier A is chosen based on tallest men from every column and shortest among them.

• Soldier B is chosen based on shortest men from every row and tallest among them.

• The height of Soldier A and Soldier B cannot be determined without additional information about the grid of soldiers.

To find and remove a loop in a Linked List, we can use Floyd's Cycle Detection Algorithm.

• Use two pointers, slow and fast, to detect if there is a loop in the Linked List

• If the two pointers meet at some point, there is a loop

• To remove the loop, set one of the pointers to the head of the Linked List and move both pointers one step at a time until they meet again

• The meeting point is the start of the loop, set the next pointer of this node to NULL to remove the loop

Use triggers to update related table on row modification.

• Create a trigger on the main table to update the related table

• Use the UPDATE statement in the trigger to modify the related table

• Ensure that the trigger is efficient and does not cause performance issues

• Test the trigger thoroughly to ensure that it works as expected

Density of a person in a social networking graph is the ratio of friends who interacted with the person to the total number of friends.

• Calculate the number of friends who interacted with the person.

• Calculate the total number of friends for that person.

• Divide the number of interacting friends by the total number of friends to get the density.

• Density = (Number of interacting friends) / (Total number of friends)