Technical Interview Questions

Project management interview questions & answers

How would you handle non-productive developers or team-members?

Align big lofty goals with their personal goals. If not, incentivize them by helping them identify the personal goals(like learning a new programming language that will be used in this project that will help her/him get motivated)
Clearly define roles and responsibilities. Assign accountability to them.
Don't be overly strictly. Put some big rules in place but don't keep overemphasizing them.
Include the team in decision making and planning process.
Do retrospective meetings to ensure what has been accomplished and what not.
Talk to them to understand if they need help.

How will you get traction from a TPM of another team?

Communicate the goals to them and what impact they are going to make. Indicate KPIs or metrics that this goals could help achieve.
Align their projects with yours and involve them into planning.
Divide the projects into roadmap and sub-stories. Make them commit to the sub-stories and ask for timelines.
Offer help if they are not able to achieve those timelines.
Glorify them when the projects are achieved within reasonable time limits. This will make them very likely to work with you again.

What are important things of consider while running a cross-team program?

Helps if roles and responsibilities are defined.
Communication is shared. And their are frequent updates. Frequent meetings of leaders, where they provide updates from their teams.
Its best if they know the mission and goals one can achieve. Report frequently on KPIs and metrics.
Encourage cross-functional training.
Celebrating major milestones and congratulating the team on achieving the goals.

How do you earn trust of your team members.

Lead by example
Communicate openly
Don't place blame on any one person. Tackle the issue at hand without pointing fingers.
Discuss trust issues.
Be available to them to discuss project goals and communicate often.
Develop team exercises.
Be calm, open, and transparent where ever possible.
Encourage mutual feedback.
Allow flexibility in choosing projects, hours.
Be patient with new employees.

How do you plan a project or program?

Under the project goals.

Align them with company goals and mission.
Define KPIs and metrics.
Prioritize goals.

Identify stakeholders and meet with them. Discuss project goals with them to see if they help achieve their goals.
Create a product roadmap.
Divide roadmap into deliverables.
Assign deliverables to functional and dev teams. Create a project schedule of the deliverables.
Identify issues or technology gaps and complete risk assessment.

Think of alternatives to avoid or minimize risk.
Think of MVPs in case project runs into delivery issues.

Present the plan to stakeholders.
Communicate the plan to the dev teams and keep things moving.

What in your opinion are three constraints of a project or program?
Its called as Project management triple constraint. Those are:

Time
Cost
Scope
4th: Meets the customers requirements. - Make it PM diamond.

Tell-tale signs that your project is going to fail:
Objectives:

Missing strategy.
No clear goals.
Leadership priority issues.
Too many projects at one time.
Constant scope changes.
Last minute major changes.

Leaders:

Team doesn't trust higher level or management.
Management or key people leaves in between the projects.

People:

Stakeholders are not interested.
No knowledge sharing.
Resource limits

How do you motivate your team of developers?

Provide them flexibility to choose the projects and times they could work on whenever possible.
Involve them in planning and important decision making if possible. Don't ask them to do it because upper management is doing it.
Help them understand what KPIs or metrics you are trying to achieve. And how it will help shape the company.
Career growth: Help them with career growth if possible. Align the career goals to the projects that are pending.
Innovation: Allow them to utilize latest tools and technologies. If they are going to conferences to learn new things let them go. Request a demo to see you are interested what they have been learning. See if you can put sometime in project planning to let them experiment with new technologies.
Create structured trainings in the organizations. Let me take online trainings and reimburse it when needed.
Provide recognition of good work.
Good infrastructure to let them work.
Empower them to make the decisions where ever possible. Don't wait on you for each and everything.

How have you contributed to the success of the project?
By:

Understanding end goals.
Understanding my role and each team's roles.
Identifying Interdependencies and stating them early on.
Cross functional and periodic communication via emails, standups, meetings.
Setting up milestones and periodic checking enabling team to collaborate well.
Accepting and managing problems.
Recognizing and rewarding the teams.

How would you increase efficiency of your development team?
By:

Document Coding and dev standards.
Implement CI integration.
Release often if possible.
Schedule demos.
Follow test driven development.
Creating detailed tasks.
Review backlog
Resolve blockers.
Have short meetings.
Support initiative
Rely and trust your team's expertise, where ever possible.

If you come about an early delay in one of your milestones what would you do?

Catch them early by monitoring the progress of the project and staying in touch with leads through out the project.
Notify stakeholders: Update them on delay and revised schedules.
Call for a meeting: Dev, technical teams, vendors, stakeholders, customers and update them on the delay.
Gather the right resources: Re-allocate the resources.
Reschedule: Check if some activities that were planned sequentially can be done parallely.
Re-prioritize: List out all the activities that are not yet done. Move the important ones to the top of the list.
Document the updated plan and send it out to everyone.

How to decide between traditional project management v/s Agile methologies?
Use traditional when:

Long and detailed planning is required.
Processes is linear and all the tasks are scheduled sequentially.
Requires a formal CM process.
Prioritization is fixed.
Customer feedback can be taken at the end and incorporated into future releases. Customer involvement is low.
Organization is very centralized.
ROI is achieved at product release.
Ex: Hardware or non-customer facing projects like infrastructure or technology changes.

Use Agile when:

Process and decision making is iterative.
Need customer feedback right away and can be incorporate right away.
Organization is de-centralized.
Prioritization changes based on business requirements and customer feedback.
Small amount of work is picked up to be done. Rest can be updated and prioritized based on inputs.
Customer involvement is high.
ROI is achieved often and is iterative. It determines what the future releases.

What are the various states of the project? - RYG. What do they stand for? How to move the project from R to G?
Green: Project is within budget, timeline, and expectation.
Yellow: Project might fallout of budget, timeline or expectation and is it risk. Requires special attention from team involved. If needed from higher ups.
Red: Some aspect of the project has fallen behind or encountered major setback or is over budget
How to move R to G: Have a plan on paper, get a buy in, and get it approved. Once everyone agrees to the new set of parameters then move it to G from R.
Some teams move G to Y or R to get feedback from upper management so that they can get their expertise involved to get it done.

Question list for Product Management Interviews

Behavioral questions list:

How you got into computer science?
What kind of technical publications (print or online) do you read on a regular basis?
What was the last book you read?
If you could recommend one resource (book, web site, etc.) to a new software developer just out of school, what would it be?
What was the most interesting project that you worked on?
What was the most challenging project that you worked on?
If you could have any job in the world, what would it be?
Tell me about your favorite project
Tell me about a something you did that was unsuccessful, a project or class that didn't go well.
Do you prefer a structured or unstructured working environment?
How do you prioritize multiple projects?
Tell me about previous jobs?
What are your greatest strengths and weaknesses?
Tell us about yourself.
Where would you like to be in five years?
How do you see yourself fitting in to this company?
Do you have any questions for me?
Why did you leave your last job?
Did you finance your own education?
Are you good with people?
Have you experience working on a group project?
What did you find hardest when working with others in a project?
What is a tool or system that you learned on your own?
How would go about finding out where to find a book in a library. (You don't know how exactly the books are organized beforehand).
Tradeoff between time spent in testing a product and getting into the market first.
What to test for given that there isn't enough time to test everything you want to?
Why do you think you are smart?
Do you want to know any thing about the company.( Try to ask some relevant and interesting question).
How long do u want to stay in USA and why?
What are your geographical preference?
What are your expectations from the job?

Product Management Interview Questions List:

Favorite product and how you would improve it.
Favorite non-technical product
Make an app that has 10x increase in downloads
Estimate number of lightbulbs in US
Estimate the revenue of XYZ company
Estimate the bandwidth needed if you built an optical fiber connection to a colony on Mars
Here's a data set. Something changed and here's the new data set. Explain what happened.
What's your favorite product? How can you improve it?
How would you got about building a startup that does XYZ
If you could start a company with $1,000,000 right now what would it be? and why?
Tell me about a product you like
Why do you like it?

how would you improve it?
how would you monetize it?

Tell me about a time you used data to solve an ambiguous problem
Tell me what you would improve about Toothpaste
Tell me about the most exciting project you've worked on in the past, and why it was the most exciting for you.
Design scenario: The alarm clock industry is really waning as of late. What could you do to curb this trend?
How many hotels are their in the US
Tell me about your background
Asked what is one of my favorite products and how I'd improve it.
You are the PM for a steaming video service. You come into the office and see that one key metric has dropped by 80%. What will you do?
How many balloons fit inside of San Francisco?
Pick your favorite gadget or piece of technology. How would you market that product now? (Marketing)
How many pairs of skis do you think there are in Austria? (Because the guy was from UK)
How many people run a marathon every year?
How much money spent in USA per year on GAS
Design an app for a community of Celiac's disease patients. Talk about a product you hate.
How will you measure the improvement?

Common themes of product management interview questions:

Product, Estimation, Vision for the common
Estimation, Coding, Product questions
Lot of behavioral and fit questions
Analytical skills(How would you do this? How you will solve that problem)
Business acumen
Some Tech
Probability questions
Permutation and combinations
Product Design
Metrics
System design
Google Products
Strategy
Approaches
Thinking out of the box
Personality

Source: Glassdoor.com

Google product management Interview questions from Glassdoor.com

How many polynomials can you fit in 3 dimensions and then once you figure that out extrapolate in n dimensions.
How would you improve XYZ Google product?
Given unlimited resources, how you fix XYZ company
What's wrong with XYZ? If you were the CEO, how would you fix it?
Estimate the rate of revolution of Earth
Favorite Google product and why?
How would you increase adoption of Google's Fiber to the Home product?
Now let's imagine you are PM of that product. And you launch a new feature (of the feature sets suggested above). Day after launch usage drop dramatically. How do you go about inquiring what happened?
What do you think about the Android vs. iOs ?
Optimize search algorithm to create an ordered list
You have a ladder of N steps (rungs). You can go up the ladder by taking either 1 step or two steps at a time, in any combination. How many different routes are there (combinations of 1 steps or 2 steps) to make it up the ladder?
Fibonacci series
Why Google?
Design scenario: Let's say you have a tv remote with 3 buttons, mute, vol up, vol down. What would you expect to happen if a user hits vol up button when its muted? Talk through the scenarios and what the user is trying to do. What would you expect to happen if you hit vol down button when it's muted?
Lets design an X, who would you improve product Y).There were a few questions designed to measure mental horsepower (Estimation, Puzzles).
Case study to test the feasibility of a new service box that communicated over HTTP and used JSON requests(2012)
How would you find a snippet of text in a webpage. Code it in any language you like.(2012)
Build a better gmail
Asked about my favorite Google Apps and how to make them better.
Asked about a hypothetical product and how I'd leverage its capabilities for launch.
You are the PM of Facebook's New feed. How will you select things that are to be shown to any user? (Lots of follow up questions)
Let's say Google is able to develop self-driving cars. What are some of the businesses you could start with that technology?
You work in Google's e-commerce business. The team is planning to enter into the hotel vending machine business. How will you design the product? (Used the CIRCLES framework to build the product design)
You are the PM of an enterprise analytics product. Your team just launched a product at end of Q4 and everyone is very exhausted from all the work that went into launching the product. Soon after the launch, the sales lead makes a request for a big feature based on customer feedback. The operations support person also circles back with a request to fix a bug. Given that you only have 2 weeks before your team goes on leave for the new year, what will you priority between the two: build new feature or fix bug? Engineering team just reported that both the actions will take 2 weeks.
You are the PM for Google Cloud developer series. Which customer will you focus on: Cloud Natives (Companies built entirely on cloud - start-ups / individuals etc.) or Legacy Enterprise (companies interested in moving to cloud)
Google wants to build a robot lawnmower. How will you do it?
Which Google product you do not like? Why? How will you improve it? Let's say you are the PM for that product. What will be your three roadmap like?
Google recently developed a technology that can detect human emotions in a 2 X 2 dimension (energy level and body movement). What are some of the products you can build using that technology? I listed 7-8 ideas and then I was asked to choose one and do the product design for that idea.
Questions focus on general cognitive ability, marketing strategy knowledge and experience, leadership skills, and Googleyness (cultural fit). Expect a mix of behavioral, hypothetical/case (e.g., "build a marketing plan for X"), and fit questions.
Challenges in previous jobs, optimal work environment I thrive in, initiatives I personally led to success
Mix of behavioral and marketing focused situational questions. Understand strategy in creating marketing campaigns for various Google products. Swipe to Unlock, Rise Above the Noise, and Decode and Conquer were helpful books to read as I was preparing! Show your passion, and have examples as to why you're a creative and analytical person.
Why google?
Name your top 5 favorite mobile apps, why do you like them? Who should Google acquire?
Take a grocery app - what would be the features you would suggest?
Choose a city and estimate how many Piano Tuners operate a business there.
How many buildings are built in California etc.

Source: Glassdoor.com

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Project management interview questions
Project management interview questions - Part 2
Scrum interview questions

Find product of all numbers in an array except self

It is a commonly asked interview question during onsite or phone interview. So the question is given an array, how will you find a product at all locations of an array without its own location.

Background:
If you are given an array: 1,2,3,4 then you are required to provide a product of all locations expect self. In this case, your response will be a,b,c,d. a will be calculated by taking product of b,c, and d. b will be calculated by taking product of a,c,d. Similarly here are other calculations:
c = a * b * d
d = a * b * c.

Brute force approach is iterate through all the locations and calculate the product skipping its own location. It can be implemented using 2 for loops and its complexity will be O(N*N). But there is a better way to do it and its mentioned in following algorithm. Idea of the algo is:

calculate the product of all locations before hand.
Iterate through the array and divide the product with the value provided at its location.

Algorithm:

First find the product of the all the values in the array.
If product is not equal to zero then proceed to step 3 or else end.
At every array location, divide the product with the number at array location. That will return the product of all locations of array expect self.

Implementation:

public class Test  {
    static int a[] = {1,2,3,4};

    public static void calculateProductExpectSelf() {
        int product = 1;
        for(int i=0; i<a.length; i++) {
            product *= a[i];
        }

        if(product != 0) {
           int b[] = new int[4];
            for(int i=0;i<a.length;i++) {
               if(a[i] != 0) {
                   b[i] = product/a[i];
                   System.out.println("\t" + b[i]);
               }
            }
        } else {

                  System.out.println("Product is zero"]);
     }

    public static void main(String args[]) {
        calculateProductExpectSelf();
    }
}

Dry Run:

array = a[] = {1,2,3,4}

Product = 1*2*3*4 = 24


In first iteration, the program will print: 24/1 = 24. 
In second iteration, the program will print: 24/2 = 12.
In third iteration, the program will print: 24/3 = 8.
In fourth iteration, the program will print: 24/4 = 6. 

Complexity:

O(N)

System Programming

Basics of Kernel
All about Grep commands
Compiler Cheat Sheet
C Cheat Sheet
C++ Cheat Sheet
Bitset in C
Shell Programming Cheat Sheet
Special features of C language
C++ basic concepts
Technical phone interview questions
Mercurial commands

Algorithm and Data Structures

Find White Spaces in Character Array
Find a character in the String
Number is prime or not
Finding Absolute Value
Notes on Sorting and Searching Algorithms
Common String Functions
Reverse a String
Product of all array location expect its own
Find a cycle in the Linked List
Find a binomial co-efficient
Counting sort algorithm
B-Tree
Find product of all locations in an array expect self

Java

Java Concepts
Java String concepts
Immutable classes in Java
Remove duplicates from the array
Telephonic phone technical interview questions
Telephonic phone technical interview questions - Part 2
Serialization & Deserialization
Jersey Package Dependencies
Observable and Observer Interface
Servlet Filter
Servlet Client Request
Spring dependencies for Maven
Java String Operations

Front End

CSS3

Gradients in CSS3
Radius Property of CSS3
2D transform in CSS3
Transition Property in CSS3
Animation in CSS3
CSS properties
Text properties in CSS3

Javascript and jQuery

jQuery Guide

Product Management

Management Concepts
Questions on Wireframes
Common Design Questions
List of Puzzles
List of Behavioral Questions
MySQL
Behavioral Question and Answers
Product Manager Estimation Questions

Miscellaneous

Must Read list

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Python is a versatile language and it pays to learn it. Most of the manual tasks can be automated via python and new functionalities can be implemented easily. Above link is a book that will help you learn it easily.

Python Tricks
A great article to learn some cool tips and tricks in python.

Web Security
Nice article to learn some basics of Web Security.

Product Manager Estimation Question: Exercise #1

If you are opening a new Walmart store, how would you decide how many cash register is needed for the store?

There are basic steps to solve this problem. They are:

Ask any clarifying questions. Work with interviewer to define the scope.
Create a main equation such as a = b * c. Divide the equations into sub parts.
Think of any edge cases.
Calculate the numbers and do a sanity check.

Starting with steps:

Questions and Answers by the candidate.

Questions and Answers by the interviewer.

Ask clarifying questions to define the scope of the problem:

Do we know if this walmart is in a suburb or city? Suburb
Do we know if there are any other walmarts in the neighborhood? Yes two more.
Are they closer to this suburb? No. Both of them are far.
Ok so in that case, many of the residents will rely on this Walmart. Yes.
Can we assume that any person is ok with waiting at the register for 4-8 mins? Yes

Create the main equation:

Number of registers = Number of people visiting the store/time taken at each register.

Break down the equations into simple sub-equations:

Two main components are: Number of people visiting the store.
Time taken at each register: 4-8 mins as clarified.
So we need to focus on number of people. Basically only a certain set of people visit the store so we can say x% of entire population visit the store.
Since we have no way of telling what is x but given that Walmart is popular choice of lower to upper middle class. We can safely assume that x=65-70% people visit Walmart because of their low prices.
Since its a suburb whose size we don't know, we are going to estimate.

US average population is 325 million. We will round it to 300 million for easier calculations.
Based on some stats I know that:

26% population live in urban areas
51% in suburban
21% in rural

Majority of population is living in suburban. Estimated number is 150 million live in suburban.
There are 50 states in USA. We can assume that each state has 50-60 suburbs and bigger ones will have 65-80 suburbs. So average is 60(round off) suburbs in each state. So total suburbs are around: 50*60= 3000 = 3k
So 150 million people live in 3k suburbs. And on average 50k people live in 1 suburb.
Only 65%(as assumed)of 50k go to Walmart. But they go as a family. So we don't need to calculate all the people. We need to calculate the households.
We can assume that each household has approximately 3 people. This brings down our number of people to 16k users.
And not all the people are at the walmart at the same time. We can say at any time only 5% of people are at a walmart = 5% of 16k = 800 approximately.
Now not everyone is checking out at the same time. Let's say only 30% of them are. this brings down the number to 240.
And not all 240 has shopping carts, they are with their families. Let's say each group has 2 people ~ 120 are in line.

Calculate the numbers and do a sanity check:

Equation: Number of registers = Number of people visiting the store/time taken at each register.
Sub equation: Number of registers = (x% of total population visit the store)/time taken at each register.
x% of total population that visit the store and are doing a checkout during busiest times are = 120
Average time taken at each register = 6 minutes.
So total registers = 120/6 = 20
Sanity check: At a walmart, I have seen 15-20 registers and our answer is 20. So this is in the ballpark number.

Final answer is = 20 registers.

Some background:

Initially I assumed 30 suburbs in each state. The count came down to 100 million people in each suburb. This is a lot. San Jose's population is 1 million. So I went back and changed the number of suburbs to 60 per state. This helped with some corrections.
I assumed 30% of suburbs population is in Walmart at any given time. Again this is a huge number. So fixed it to 5%.
Then assumed 50% of them are checking out at the same time so fixed it to 30% as well.

Let me know your thoughts and let me know in comment section on how you will solve this problem.

Quick Cheatsheet on some Javascript Basics

1) Global objects can be accessed via this operator in javascript.

2) Global properties that return a simple value and have no methods are:
Infinity, NaN, undefined, null

3) How to create a variable:
var myNameVariable = ‘name1’;
//Re-assigning the value:
myNameVariable = ‘name2’;

4) Primitive data types that are supported in Javascript are:
Boolean, Null, Undefined, Number, String, Symbol, Object

Boolean type can take true or false
Null can take exactly one value: null
Integers are 16-bit unsigned integer values
Object: It's like an object oriented programming concept of object.

5) Comments: Following are 2 types of creating comments.

/* */
//

6) Mathematical operators:

add/concatenation: +
subtract: -
multiple: *
divide: /
assignment operator: =
Identity Operator: ===
Negation: !
Not equal: !==

7) How to define a function
function testFunc() {
alert(“Test”);
}