Microsoft Corporation Software Developer Intern Interview Questions, Process, and Tips

Round duration - 90 minutes
Round difficulty - Medium

The round consists of 3 coding questions and the test was conducted on mettl platform. There was no sectional time limit for the coding questions. Every student got randomly 3 coding questions and none of the students got the same set of questions. The test was online with audio and video both on for continuous monitoring.

Q1. 
Mean, Median, Mode Calculation
You are given an array 'ARR' consisting of 'N' integers. Your task is to calculate the three statistical measures for the given array:
1. Mean - Implement the function mean...read more
Ans. 
Implement functions to calculate mean, median, and mode of an array of integers.
• Implement a function mean() to calculate the mean of the array by summing all elements and dividing by the total count.

• Implement a function median() to calculate the median of the array by sorting the array and finding the middle element(s).

• Implement a function mode() to find the mode of the array by counting frequencies and returning the s
Answered by AI
Add your answer
Q2. 
Nth Term of Geometric Progression (GP) Series
Determine the Nth term of a geometric progression (GP) series given the first term, common ratio, and the term number.
Explanation:
The general form of a GP...read more
Ans. 
Calculate the Nth term of a geometric progression series given the first term, common ratio, and term number.
• Use the formula for the Nth term of a GP series: A * (R^(N-1))

• Ensure to take the modulo 10^9 + 7 as the output

• Handle multiple test cases efficiently within the given time limit
Answered by AI
Add your answer
Q3. 
Dice Throw Problem Statement
You are provided with D dice, each having F faces numbered 1 to F, inclusive. Your task is to determine the number of possible ways to roll the dice such that the sum of the f...read more
Ans. 
The problem involves finding the number of ways to achieve a target sum by rolling a given number of dice with a certain number of faces.
• Use dynamic programming to keep track of the number of ways to achieve each sum from 1 to the target sum.

• Iterate through the dice and faces to update the number of ways to reach each sum.

• Return the number of ways to achieve the target sum modulo 10^9 + 7.
Answered by AI
Add your answer

Round duration - 50 minutes
Round difficulty - Medium

This round was based on data structures and some discussion regarding the projects. The interviewer was very calm and listened very carefully to the solutions. There was a lot of discussion on my projects and the interviewer seems to be very interested in knowing about the workflows of my projects.

Q1. 
Identical Trees Problem Statement
Given two binary trees with 'N' and 'M' nodes respectively, determine if the two trees are identical. Return true if they are identical, otherwise return false.
Input:
...read more
Ans. 
Check if two binary trees are identical by comparing their nodes in level order.
• Traverse both trees in level order and compare corresponding nodes for equality

• Use a queue to keep track of nodes to be compared

• Return false if nodes are not equal or if one tree has more nodes than the other
Answered by AI
Add your answer
Q2. 
Distinct Subsequences of a String
Given a string S of length N that may contain duplicate alphabets, your task is to compute the count of distinct subsequences of this string.
Example:
Input:
S = "deed...read more
Ans. 
Compute the count of distinct subsequences of a string with possible duplicates.
• Use dynamic programming to keep track of distinct subsequences.

• Consider the cases where the current character is included or excluded in the subsequence.

• Use a hashmap to store the last occurrence index of each character to handle duplicates efficiently.
Answered by AI
Add your answer

Round duration - 50 minutes
Round difficulty - Medium

This round was also based on data structures and the interviewer was not responding as much as in the first round so that I should think on my own that whether I am on right track or not. In this round also there was a deep discussion on one of my web development with machine learning project. So don't panic in these situations If the interviewer is not responding much because he is noting down every tiny detail of your written code.

Q1. 
Delete Kth Node from End of Linked List
This problem requires you to delete the Kth node from the end of a given singly linked list with N nodes containing integer data.
You are asked to efficiently remo...read more
Ans. 
To delete the Kth node from the end of a singly linked list efficiently without finding the length of the list and using O(1) extra space.
• Use two pointers approach - one pointer moves K steps ahead of the other.

• When the first pointer reaches the end, the second pointer will be at the Kth node from the end.

• Adjust the pointers to remove the Kth node efficiently.

• Ensure to handle edge cases like deleting the head or tail n...read more
Answered by AI
Add your answer

Round duration - 30 minutes
Round difficulty - Medium

This was an HR/Coding round and was the final one. The coding question was to find the nth node from the end of the linked list which is similar to the one asked in the previous round. The interview started with 2-3 HR questions and after I answered all of them, there was a serious discussion on my projects like why did you chose this project, what are its advantages, was it able to solve the existing problem. I answered all the project related queries very calmly and he was satisfied.

Round duration - 60 Minutes
Round difficulty - Easy

It was an online technical interview focusing on DS and algorithms. They asked two questions in this round. He also asked me to code both the questions. I solved both questions with confidence.
They also gave a puzzle to solve. Out of 32 they selected 22 students along with me.

Q1. 
Spiral Matrix Problem Statement
You are given a N x M matrix of integers. Your task is to return the spiral path of the matrix elements.
Input
The first line contains an integer 'T' which denotes the nu...read more
Ans. 
The task is to return the spiral path of elements in a given matrix.
• Iterate through the matrix in a spiral path by adjusting the boundaries of rows and columns.

• Keep track of the direction of traversal (right, down, left, up) to cover all elements.

• Print the elements in the spiral path as you traverse the matrix.

• Handle edge cases like when the matrix is a single row or column.
Answered by AI
Add your answer
Q2. You are given a certain number of eggs and a building with a number of floors. The goal is to find the highest floor from which you can drop an egg without breaking it. What is the optimal strategy to mini...read more
Ans. 
Optimal strategy to minimize number of drops to find highest floor an egg can be dropped without breaking.
• Start by dropping the first egg from a lower floor and incrementally increase the floor until it breaks.

• Once the first egg breaks, use the second egg to perform a binary search between the last successful drop and the floor below the breaking point.

• This strategy ensures the minimum number of drops required to find
Answered by AI
Add your answer

Round duration - 90 minutes
Round difficulty - Easy

The test was held on Mettl Platform in online mode from 10:00-10:15 AM joining time for 90 minutes.

Q1. 
Infix to Postfix Conversion
Convert a given infix expression, represented as a string EXP, into its equivalent postfix expression.
Explanation:
An infix expression is formatted as a op b where the opera...read more
Ans. 
Convert infix expression to postfix expression.
• Use a stack to keep track of operators and operands.

• Follow the rules of precedence for operators.

• Handle parentheses to ensure correct order of operations.
Answered by AI
Add your answer
Q2. 
Most Frequent Word Problem Statement
You are given two strings 'A' and 'B' composed of words separated by spaces. Your task is to determine the most frequent and lexicographically smallest word in string ...read more
Ans. 
Find the most frequent and lexicographically smallest word in string 'A' that is not present in string 'B'.
• Split strings 'A' and 'B' into words

• Count frequency of each word in 'A'

• Check if word is not in 'B' and is the most frequent and lexicographically smallest

• Return the word or -1 if no such word exists
Answered by AI
Add your answer
Q3. 
Regular Expression Match Problem Statement
Given a string str and a string pat, where str may contain wildcard characters '?' and '*'.
If a character is '?', it can be replaced with any single character....read more
Ans. 
Given a string with wildcard characters, determine if it can be transformed to match another string.
• Iterate through both strings simultaneously, handling wildcard characters '?' and '*' accordingly.

• Use dynamic programming to keep track of matching characters.

• Handle cases where '*' can match an empty sequence or multiple characters.

• Return true if at the end both strings match, false otherwise.
Answered by AI
Add your answer

Round duration - 60 minutes
Round difficulty - Medium

Timing-> EVENING(5 TO 6)
The interviewer was very sweet and calm.

Q1. 
Cycle Detection in a Singly Linked List
Determine if a given singly linked list of integers forms a cycle or not.
A cycle in a linked list occurs when a node's next points back to a previous node in the ...read more
Ans. 
Detect if a singly linked list forms a cycle by checking if a node's next pointer points back to a previous node.
• Use Floyd's Cycle Detection Algorithm to determine if there is a cycle in the linked list.

• Maintain two pointers, one moving at twice the speed of the other.

• If the two pointers meet at any point, there is a cycle in the linked list.
Answered by AI
Add your answer
Q2. 
Boundary Traversal of a Binary Tree
Given a binary tree of integers, your task is to return the boundary nodes of the tree in Anti-Clockwise direction starting from the root node.
Input:
The first line ...read more
Ans. 
Return the boundary nodes of a binary tree in Anti-Clockwise direction starting from the root node.
• Traverse the left boundary nodes in a top-down manner

• Traverse the leaf nodes in a left-right manner

• Traverse the right boundary nodes in a bottom-up manner

• Avoid duplicates in boundary nodes
Answered by AI
Add your answer

Round duration - 60 minutes
Round difficulty - Medium

It was a video call round, that began with a brief introduction of the interviewer followed by mine. Then the interviewer asked me to solve 2 data structure questions in a text editor while sharing my screen. Also, we had a brief discussion of the time complexity of the programs I had written, which I had to optimize to the best time complexity as well.

Q1. 
Spiral Matrix Problem Statement
You are given a N x M matrix of integers. Your task is to return the spiral path of the matrix elements.
Input
The first line contains an integer 'T' which denotes the nu...read more
Ans. 
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, right, bottom, and left sides of the matrix.

• Handle cases where the matrix is not a square (N != M) separately.

• Consider edge cases like single row, single column, and empty matrix.
Answered by AI
Add your answer
Q2. 
Sort 0 1 2 Problem Statement
Given an integer array arr of size 'N' containing only 0s, 1s, and 2s, write an algorithm to sort the array.
Input:
The first line contains an integer 'T' representing the n...read more
Ans. 
Sort an array of 0s, 1s, and 2s in linear time complexity.
• Use three pointers to keep track of the positions of 0s, 1s, and 2s in the array.

• Iterate through the array and swap elements based on the values encountered.

• This approach sorts the array in a single scan without using any extra space.
Answered by AI
Add your answer

Round duration - 60 minutes
Round difficulty - Easy

It was a face-to-face round in the Hyderabad Office at 8 in the morning. This round consisted of various types of questions. It began with a brief description of my interest in technology and a discussion about any major problems I faced working and how I resolved it. Then it continued with various data structure questions, followed by operating system, database, and system design questions. I had majorly worked with the project Jarvis Personal Assistant, so I was asked to design the complete workflow of the project.

Q1. 
Mirror String Problem Statement
Given a string S containing only uppercase English characters, determine if S is identical to its reflection in the mirror.
Example:
Input:
S = "AMAMA"
Output:
YES
Ex...read more
Ans. 
Determine if a given string is identical to its reflection in the mirror.
• Iterate through the string and compare characters from start and end simultaneously.

• If characters are not equal, return 'NO'.

• If all characters match, return 'YES'.
Answered by AI
Add your answer

Round duration - 90 minutes
Round difficulty - Medium

This round was of 90 minutes, consisting of 3 coding questions from easy to medium level. It was conducted in the morning hours. The invigilators were the staff of my college only. The platform was very smooth and almost all the programming languages were allowed.

Q1. 
Valid Parentheses Problem Statement
Given a string 'STR' consisting solely of the characters “{”, “}”, “(”, “)”, “[” and “]”, determine if the parentheses are balanced.
Input:
The first line contains an...read more
Ans. 
The task is to determine if a given string consisting of parentheses is balanced or not.
• Use a stack data structure to keep track of opening parentheses.

• Iterate through the string and push opening parentheses onto the stack.

• When encountering a closing parenthesis, pop the top element from the stack and check if it matches the corresponding opening parenthesis.

• If the stack is empty at the end of the iteration and all par...read more
Answered by AI
Add your answer
Q2. 
Trapping Rain Water Problem Statement
You are given a long type array/list ARR of size N, representing an elevation map. The value ARR[i] denotes the elevation of the ith bar. Your task is to determine th...read more
Ans. 
Calculate the total amount of rainwater that can be trapped between given elevations in an array.
• Iterate through the array and calculate the maximum height on the left and right of each bar.

• Calculate the amount of water that can be trapped at each bar by taking the minimum of the maximum heights on the left and right.

• Sum up the trapped water at each bar to get the total trapped water for the entire array.
Answered by AI
Add your answer
Q3. 
Travelling Salesman Problem
Given a list of cities numbered from 0 to N-1 and a matrix DISTANCE consisting of 'N' rows and 'N' columns, representing the distances between each pair of cities, find the sho...read more
Ans. 
Implement a function to find the shortest route visiting each city exactly once and returning to the starting city.
• Use backtracking to explore all possible routes and find the minimum distance.

• Keep track of visited cities to ensure each city is visited exactly once.

• Consider pruning techniques like dynamic programming to optimize the solution.

• Example: Start at city 0, visit cities 1 and 2 in any order, and return to cit...read more
Answered by AI
Add your answer

Round duration - 60 minutes
Round difficulty - Easy

This round was a group fly round. Team from Microsoft came for invigilation and guidance. We were divided into small groups, and a mentor was allotted to us. There were 2 questions and time was 60 minutes. First question was based on system design and second one was coding question. We were asked to write on paper and discuss with mentors. We were marked on the basis of how we discussed our ideas with our mentor and how clearly we presented our idea.

Q1. Design a search engine for a global retail application. Please include:
• Assumptions
• System considerations
• Design components
Ans. 
Design a search engine for a global retail application.
• Assumptions: assume the search engine will need to handle a large volume of products and users from around the world

• System considerations: scalability, speed, relevance of search results, multi-language support

• Design components: indexing system, query processing, ranking algorithm, user interface
Answered by AI
Add your answer
Q2. 
Longest Palindromic Subsequence Problem Statement
Ninja receives a PS5 from Santa, locked in a safe with a password. The password is the length of the longest palindromic subsequence in the given string S...read more
Ans. 
The task is to find the length of the longest palindromic subsequence in a given string.
• Iterate through the string and create a 2D array to store the lengths of palindromic subsequences.

• Use dynamic programming to fill the array based on the characters of the string.

• The final answer will be the value at the last index of the array.

• Example: For input 'CACBDBA', the longest palindromic subsequence is 'CBDC', so the output
Answered by AI
Add your answer

Round duration - 30 minutes
Round difficulty - Medium

The interview was early in the morning. The environment was very tensed, we all were very nervous for the first round of interview. The interviewers were very friendly, they were helping us a lot .

Q1. 
Binary Search Tree Insertion
Given the root node of a binary search tree and a positive integer, you need to insert a new node with the given value into the BST so that the resulting tree maintains the pr...read more
Ans. 
Insert a new node with a given value into a binary search tree while maintaining the properties of a BST.
• Traverse the BST starting from the root node to find the correct position for insertion.

• Compare the value to be inserted with the current node's value to determine whether to go left or right.

• Create a new node with the given value and insert it at the appropriate position in the BST.

• Ensure that the resulting tree ma...read more
Answered by AI
Add your answer

Round duration - 30 minutes
Round difficulty - Easy

This round was conducted in the afternoon. The environment was friendly. Interviewer was very friendly and helping.

Q1. 
Sort Stack Problem Statement
You are given a stack S. Your task is to sort the stack recursively in descending order.
Constraints:
• Looping through the stack is not allowed.
• Return the stack sorted ...read more
Ans. 
Sort a given stack in descending order recursively without using loops.
• Use recursion to pop elements from the stack and insert them in the correct position.

• Maintain a temporary stack to hold elements while sorting.

• Compare the top element of the stack with the top element of the temporary stack to insert in descending order.
Answered by AI
Add your answer

Round duration - 30 minutes
Round difficulty - Medium

I was conducted in the evening. The interviewer was very friendly and asked me questions mostly about me and my future plans.