100+ Interview Questions and Answers

You are given a vector of 'N' integers denoting the number of buses that can be boarded from the i-th position. The bus stops only at stops whose number is a multiple of the bus stop number from which the ...read more

Chess tournament is going to be organized in Ninjaland. There will be C chess players going to attend the tournament. All the players will be staying in a hotel. The hotel has N free room...read more

Write a function that calculates the corresponding day of the week for any particular date in the past or future.

For example, for the date 28th August 2020 happens to be Friday. Hence the expect...read more

There are ‘n’ fruit trees that are planted along a road. The trees are numbered from 0 to n-1. The type of fruit each tree bears is represented by an uppercase character of the English alphabe...read more

You are given two Strings 'P' and 'Q' of equal length. Your task is to check whether String 'P' can be converted into String 'Q' by cyclically rotating it to t...read more

You are given an array of 'N' integers denoting the heights of the mountains. You need to find the length of the longest subarray which has the shape of a mountain.

A mountain subarray ...read more

There are ‘N’ people at a party. Each person has been assigned a unique id between 0 to 'N' - 1(both inclusive). A celebrity is a person who is known to everyone but does not know anyone at...read more

Design and implement a data structure which supports the following operations:

insert(X): Inserts an element X in the data structure and returns true if the ...read more

You are given an array of strings. Your task is to find the number of unique strings.

A string is considered unique if it cannot be formed from any other strin...read more

You are given an array consisting of 'N' distinct positive integers and a number 'K'. Your task is to find the kth largest element in the array.

Example:

Consider the ar...read more

You are given an array Arr consisting of n integers, you need to find all the distinct triplets present in the array which adds up to zero.

An array is said to have a triplet {arr...read more

You're given a string 'STR' containing ‘0’, ‘1’ and ‘?’ special characters. Your task is to generate all the strings that are possible by replacing the special character ...read more

You have been given a binary tree of integers. Your task is to calculate the sum of all the leaf nodes which are present at the deepest level of this binary tree. If there are ...read more

You are given an array 'ARR' of integers of length N. Your task is to find the first missing positive integer in linear time and constant space. In other words, find the lowest positive in...read more

You are given an array (ARR) of length N, consisting of integers. You have to find the sum of the subarray (including empty subarray) having maximum sum among all subarrays.

A subarray is a...read more

You are given a positive integer 'N'. Your task is to find the number of strings of length ‘N’ that can be formed using only the characters ‘a’, ‘b’ and ‘c’. The strings formed should be such that ...read more

You are Harshad Mehta’s friend. He told you the price of a particular stock for the next ‘N’ days. You can either buy or sell a stock. Also, you can only complete at most 2-transactions. Find...read more

You have given a Singly Linked List of integers, determine if it forms a cycle or not.

A cycle occurs when a node's next points back to a previous node in the list. The linked li...read more

You have been given a singly linked list which may or may not contain a cycle. You are supposed to return the node where the cycle begins (if a cycle exists).

A cycle occurs whe...read more

Given a sequence of numbers ‘ARR’. Your task is to return a sorted sequence of ‘ARR’ in non-descending order with help of the merge sort algorithm.

Example :

Merge Sort Algorithm - Merge sort is a Div...read more

You have been given an integer 'N'. Find the nearest multiple of 10 to the given integer 'N'.

Note:

If there are multiple answers, find the smallest one. For example, if N = 35, both 30 an...read more

You are given an arbitrary binary tree consisting of N nodes where each node is associated with a certain integer value from 1 to 9. Consider each root to leaf path as a number.

For example:

 1 ...read more

You are given D dice, each having F faces numbered 1 to F, both inclusive. The task is to find the possible number of ways to roll the dice together such that the sum of face-up numbers equal the giv...read more

You are given an integer 'N'. For a given 'N' x 'N' chessboard, find a way to place 'N' queens such that no queen can attack any other queen on the chessboard.

A queen can be killed when it lies in the ...read more

You are given a string “S” containing only digits from 0 to 9. Your task is to find all possible IP addresses that can be obtained from S in lexicographical order. If no valid IP address can be genera...read more

The Look-And-Say sequence is a sequence of positive integers. The sequence is as follows:

1, 11, 21, 1211, 111221, 312211, 13112221,...

This sequence is constructed in the following way:

Th...read more

You are given a binary tree consisting of integer values. Your task is to convert the given binary tree into a linked list where the nodes of the linked list follow the same order as the pre-...read more

Given a string 'S' and a list 'wordList' that consists of 'N' distinct words. Let 'Wi' denote word at index 'i' in 'wordList'. For each word 'Wi' in 'wordList', you n...read more

You have been given two singly Linked Lists, where each of them represents a positive number without any leading zeros.

Your task is to add these two numbers and print...read more

You are given a list of “N” strings A. Your task is to check whether you can form a given target string using a combination of one or more strings of A.

Note :

You can use any string of A multiple tim...read more

You are given an array(ARR) of length 'N', consisting of non-negative integers. Using only these given numbers, rearrange the numbers in such a way that th...read more

You are given some information about the rooms of a military camp. The rooms are numbered from 0 to 'N-1'. Each room contains keys to some other rooms. You can visit a room only if you have a key to that r...read more

You have been given the prices of 'N' stocks in an array where each array element represents the stock price for that day. You need to find the maximum profit which you can make by buyin...read more

You are given a non-empty binary tree where each node has a non-negative integer value. Return the maximum possible sum of path between any two leaves of the ...read more

You have been given the preorder and inorder traversal of a binary tree. Your task is to construct a binary tree using the given inorder and preorder tra...read more

You have been given an array/list of strings 'inputStr'. You are supposed to return the strings as groups of anagrams such that strings belonging to a particular group are anagrams of one another....read more

You have given a singly linked list and two integers 'N' and 'M'. Delete 'N' nodes after every 'M' node, or we can say more clearly that traverse the linked list suc...read more

You are given a path to a file/directory in Unix-style of length N, In a Unix-style file system, a dot(.) refers to the current directory. A double dot(..) refers to the previous directory...read more

Given a number ‘grayNumber’. Find the gray code sequence.

Conditions for a gray code sequence :

1. Gray code sequence contains numbers from 0 to 2^'grayNumber'-1 in bit/binary form. 2. Two consecutive ...read more

You are given a stream of 'N' integers. For every 'i-th' integer added to the running list of integers, print the resulting median.

Print only the integer part of the median.

Input Format :

The fi...read more

Let A[0 ... n-1] be an array of n distinct positive integers. If i < j and A[i] > A[j] then the pair (i, j) is called an inversion of A (where i and j are indexes of A). Given an integer array A...read more

You are given an array of integers 'ARR' of size 'N' and another integer 'K'. Your task is to find and return 'K'th smallest value present in the array.

Note: All the elements in the array a...read more

You have been given a binary tree of 'N' unique nodes and a Start node from where the tree will start to burn. Given that the Start node will always exist in the tree, your task is to print the...read more

Ninja is learning tree data structure these days. While learning, she came across learn about the Binary Search tree. She found BST quite interesting. She decided to make her own Binary Search...read more

You have been given a long type array/list 'ARR' of size 'N'. It represents an elevation map wherein 'ARR[i]' denotes the elevation of the 'ith' bar. Print the total amount of rainwater that ...read more

You are given two arrays of coefficients and degrees of a polynomial expression. You need to simplify the polynomial in general form by evaluating and simplifying the expression.

For Exam...read more

Given a binary tree. Print the Left View of the Tree.

Example :

If the input tree is as depicted in the picture: 

The Left View of the tree will be: 2 35 2 

Input format :

Elements in t...read more

You are given a single non-negative integer ‘N’ who’s binary representation consists of a single ‘1’ digit and the rest of the digits are ‘0’s. Your task is to find the position of the only...read more

You are given a list of ‘transactions’ between ‘n’ number of friends. who have to give each other money. The list consists of data of receiver, sender, and transaction.

Your task is to minimiz...read more

You have been given a binary tree of 'N' nodes. Print the Spiral Order traversal of this binary tree.

For example

For the given binary tree [1, 2, 3, -1, -1, 4, 5, -1, -1,...read more

You are provided with a Binary Search Tree (BST), all you have to do is to convert it into the sorted doubly linked list (DLL).

For Example:

Consider the above BST, it will be converted into t...read more

You are given a matrix of size N * M. Can you count the number of squares in it?

As the count will be very large, so compute it with modulo 10^9 + 7.

For Example:

Let N = 3 and M = 5 The number of ...read more

You are given a N x M matrix of integers, return the spiral path of the matrix

Example Of Spiral Path

Input Format:

The first line contains an integer 'T' which denotes the number of test cases or...read more

There is a one-dimensional garden of length 'N'. On each of the positions from 0 to 'N', there is a fountain, and this fountain’s water can reach up to a certain range as explained further. In ...read more

You need to design a global auditorium booking platform, which could be booked from anywhere in the world. It can host multiple shows at once as it has 2 stages with different seating capacity. The...read more

You are given the schedule of N meetings with their start time Start[i] and end time End[i]. But you have only 1 meeting room. So, you need to tell the meeting numbers you can organize in the gi...read more

You are given the arrival and departure times of N trains at a railway station in a day. You need to find the minimum of platforms required for the railway station such that no ...read more

Ninja has to design a 2 players game Tic-Tac-Toe played on an ‘N’ * ‘N’ grid.

Ninja has to assume the following rules while playing the game:

This game is played between two people (Player 1 a...read more

You are given an array 'ARR' of positive integers, each of which represents the number of liters of water in that particular bucket, we have to make the liters of water in every bucket equal.

We are allowe...read more

You are given a starting position for a rat which is stuck in a maze at an initial point (0, 0) (the maze can be thought of as a 2-dimensional plane). The maze would be given in the form of a squar...read more

You are given a string 'S' and you need to return the length of the longest duplicate substring in the given string. The occurrence of duplicate sub-strings can overlap also.

If there...read more

Ninja is an avid story lover. Today, he decides to go to the famous Storyteller of Ninjaland to listen to new stories. The Storyteller takes 'Y' coins to tell one story. The Storytelle...read more

You are given a non-negative integer ‘NUM’ in the form of a string and provided with an integer ‘K’. You need to find out the smallest integer possible by removing exactly ‘K’ digits from ‘NUM.’

What are the different operating systems? Batched operating systems
Distributed operating systems
Timesharing operating systems
Multi-programmed operating systems
Real-time operating systems

Given an integer matrix of size m*n, you need to find out the value of minimum cost to reach from the cell (0, 0) to (m-1, n-1).

From a cell (i, j), you can move in three directions : (i+1, j), (i,...read more

Write a program to do basic string compression. For a character which is consecutively repeated more than once, replace consecutive duplicate occurrences with the count of repetitions.

For e.g...read more

What is a process?
What is a program?
Difference between a program and a process.
What is a thread?
What are the different states in a process life cycle?

What is paging?

How virtual memory works ?

Why are you using SQL in your project and not NoSQL ?

How will it effect your app , and what changes need to make in order to convert SQL to No SQL DB?...read more

Three Questions were asked in this round: -

1. Why do you want Microsoft?

2. What are your career goals?

3. Why will you not accept the other offer you already have from a banking company?

What are semaphores?
What are the different types of semaphores?
What is a mutex?
What is a deadlock and how to handle it?

1. When does deadlock occur?
2. What is the difference between process and threads?

1.What is the difference between static polymorphism and runtime polymorphism?
2. What is a copy constructor? Tell any one use of it.
3. Define Encapsulation.

What is an abstract method?
What is polymorphism?
What is encapsulation?

You are given a graph with N vertices numbered from 1 to N and M edges. You have to colour this graph in two different colours, say Blue and Red such that no two vertices connected by an edge is...read more

Given an array. Replace all the elements of the array with the product of all numbers except the number at that position. Do not use the division operator.

Given a binary tree, convert it to its sum tree. That is, replace every node data with sum of its immediate children, keeping leaf nodes 0. And then return its preorder.

You want to design a game, 2D game. There are many objects in on the screen. You need to find whether these objects are overlapped or not. Size of the screen is given.
For simplicity, take the sh...read more

Write an SQL query to fetch records that are present in one table but not in another table

SELECT * FROM EmployeeSalary
MINUS
SELECT * FROM ManagerSalary;