Interview at Google
Google
Interview Preparation:
All candidates will have the chance to highlight strengths in
four different areas:
·
General cognitive
ability: We ask open-ended questions to learn how you approach and solve
problems. And there’s no one right answer—your ability to explain your thought
process and how you use data to inform decisions is what’s most important.
·
Leadership: Be
prepared to discuss how you have used your communication and decision-making
skills to mobilize others. This might be by stepping up to a leadership role at
work or with an organization, or by helping a team succeed even when you
weren’t officially the leader.
·
Role-related
knowledge: We’re interested in how your individual strengths combine with your
experience to drive impact. We don’t just look for how you can contribute
today, but how you can grow into different roles—including ones that haven’t
even been invented yet.
·
Googleyness: Share how
you work individually and on a team, how you help others, how you navigate
ambiguity, and how you push yourself to grow outside of your comfort zone.
For software engineering candidates, we want to understand your coding skills and technical areas of expertise,
including tools or programming languages and general knowledge on topics like
data structures and algorithms. There's generally some back and forth in
these discussions, just like there is on the job, because we like to push each
other's thinking and learn about different approaches. So be prepared to talk
through your solutions in depth. Push your own boundaries and find the best
answer—that’s probably how you work anyway.
Throughout the interview process, feel free to ask your
interviewers for clarification to make sure you fully understand their
questions. And feel free to interview us, too. Ask questions—about the work,
about the team, about the culture—that will help you decide whether the job
will be right for you.
How
to prepare
Here's our advice to
help you be ready for your interview.
·
Predict the future: You can anticipate 90% of the interview
questions you’re going to get. “Why do you want this job?” “What’s a tough
problem you’ve solved?” If you can’t think of any, Google “most common interview
questions.” Write down the top 20 questions you think you’ll get.
·
Plan: For every question on your list, write down your answer. That
will help them stick in your brain, which is important because you want your
answers to be automatic.
·
Have a backup plan: Actually, for every question, write down
THREE answers. Why three? You need to have a different, equally good answer for
every question because the first interviewer might not like your story. You
want the next interviewer to hear a different story and become your advocate.
·
Explain: We want to understand how you think, so explain your thought
process and decision making throughout the interview. Remember we’re not only
evaluating your technical ability, but also how you approach problems and try
to solve them. Explicitly state and check assumptions with your interviewer to
ensure they are reasonable.
·
Be data-driven: Every question should be answered with a
story that demonstrates you can do what you’re being asked about. “How do you
lead?” should be answered with “I’m a collaborative/decisive/whatever leader.
Let me tell you about the time I … ”
·
Clarify: Many of the questions will be deliberately open-ended to
provide insight into what categories and information you value within the
technological puzzle. We’re looking to see how you engage with the problem and
your primary method for solving it. Be sure to talk through your thought
process and feel free to ask specific questions if you need clarification.
·
Improve: Think about ways to improve the solution you present. It’s
worthwhile to think out loud about your initial thoughts to a question. In many
cases, your first answer may need some refining and further explanation. If
necessary, start with the brute force solution and improve on it — just let the
interviewer know that's what you're doing and why.
·
Practice: Everyone gets better with practice. Practice your interview
answers—out loud—until you can tell each story clearly and concisely.
·
Coding practice: You can find sample coding questions on sites
like CodeLab, Quora, and Stack Overflow. The book “Cracking the Coding
Interview” is also a good resource. You won’t have access to an IDE or compiler
during the interview so practice writing code on paper or a whiteboard. Be sure
to test your code and ensure it’s easily readable without bugs. Don’t stress
about small syntactical errors like which substring to use for a given method
(e.g. start, end or start, length) — just pick one and let your interviewer
know.
·
Coding: You should know at least one programming language really well,
preferably C++, Java, Python, Go, or C.
You will be expected to know APIs,
Object Orientated Design and Programming, how to test your code, as well as
come up with corner cases and edge cases for code. Note that we focus on
conceptual understanding rather than memorization.
·
Algorithms: Approach the problem with both bottom-up and top-down
algorithms. You will be expected to know the complexity of an algorithm and how
you can improve/change it. Algorithms that are used to solve Google problems
include sorting (plus searching and binary search), divide-and-conquer, dynamic
programming/memoization, greediness, recursion or algorithms linked to a
specific data structure. Know Big-O notations (e.g. run time) and be ready to
discuss complex algorithms like Dijkstra and A*. We recommend discussing or
outlining the algorithm you have in mind before writing code.
·
Sorting: Be familiar with common sorting functions and on what kind of
input data they’re efficient on or not. Think about efficiency means in terms
of runtime and space used. For example, in exceptional cases insertion-sort or
radix-sort are much better than the generic QuickSort/MergeSort/HeapSort
answers.
·
Data Structures: You should study up on as many data
structures as possible. Data structures most frequently used are arrays, linked
lists, stacks, queues, hash-sets, hash-maps, hash-tables, dictionary, trees and
binary trees, heaps and graphs. You should know the data structure inside out,
and what algorithms tend to go along with each data structure.
·
Mathematics: Some interviewers ask basic discrete math questions. This is
more prevalent at Google than at other companies because counting problems,
probability problems and other Discrete Math 101 situations surround us. Spend
some time before the interview refreshing your memory on (or teaching yourself)
the essentials of elementary probability theory and combinatorics. You should
be familiar with n-choose-k problems and their ilk.
·
Graphs: Consider if a problem can be applied with graph algorithms like
distance, search, connectivity, cycle-detection, etc. There are three basic
ways to represent a graph in memory (objects and pointers, matrix, and
adjacency list) — familiarize yourself with each representation and its pros
and cons. You should know the basic graph traversal algorithms, breadth-first
search and depth-first search. Know their computational complexity, their
tradeoffs and how to implement them in real code.
·
Recursion: Many coding problems involve thinking recursively and
potentially coding a recursive solution. Use recursion to find more elegant
solutions to problems that can be solved iteratively.
Courtesy : google
