LeetCode Python Solutions for Data Science

How does a data scientist use LeetCode to practice their python skills for their data science interviews?

Using LeetCode To Practice Python Questions

LeetCode has a huge repository of real interview questions. These questions have been asked by popular tech companies like Amazon, Google, Microsoft, Facebook, and more. Leetcode is designed for software developers and provides an amazing resource of over 1599 algorithm-based questions for software developers with various languages supported. Python and SQL are the two most popular coding languages for data scientists. So in order to improve our SQL and python skills and to prepare for an interview, Leetcode is often used.

However, can a data scientist use LeetCode to improve their Python skills for their next data science interview?

For SQL practice, mentioned in a previous article (How To Use LeetCode For Data Science SQL Interviews), their database resource and the primary way to practice SQL questions is leetcode.com/problemset/database.

LeetCode Python Algorithm Problems For Data Science

To improve your python skills as a data scientist using Leetcode, the Algorithm section is really the only section you can use (https://leetcode.com/problemset/algorithms/). The main table of questions is by default algorithms. The main table of questions defaults to algorithms, because software developers typically need to practice algorithms for their interviews. If you're new to algorithms, then this hands on-course will be a good place to start. That said, not all data scientists need to be algorithms experts.

Algorithms include reversing a list, linked lists, recursion techniques, and many more. These are great skills to have even for data scientists, especially as we’re trending towards data scientists becoming full stack and needing to have software development skills. But the core skill set of a data scientist isn’t algorithms -- it’s not how to reverse a list -- it’s how to manipulate data to turn data into insights. The data we deal with aren’t just a few arrays with random numbers for us to manipulate. The data we wrangle are often stored in various data structures like JSONs, dictionaries, and database tables. We need to understand how to access those tables and manipulate them to answer questions like “Find the share of active monthly users in the US for the last 3 months” and “Find all the users that ordered the most items from our marketing campaigns”. These questions deal with different data types like dates, decimals, and text, and need to be aggregated in such a way that someone can make decisions from its output. Leetcode will get you better at writing python but since the questions are focused on algorithms for software developers, it won’t get you better at wrangling data to drive insights.

That being said, here’s what you can do on LeetCode to practice python.

Leetcode To Practice Python Problems

Many aspiring data scientists start their data science journey by learning the Python language. The reason behind this is many companies use Python language for data science work. When you apply for a data scientist position, your recruiter would need you to possess Python knowledge. In this case, most people visit LeetCode to practice Python programming language for data science. But do you know it can take hours to navigate through the huge amount of algorithm problems designed specifically for software developers? Out of 2400 algorithm questions, there are about 1000 questions that have official solutions. Then comes browsing through all these solutions because a lot of solutions are not available in Python.

How to use Leetcode to practice python

Here are some tips that can help you while practicing LeetCode questions with Python.

Python Solutions on LeetCode

It’s hard to find questions that have official python solutions. It’s almost like a trial and error to find questions with python solutions. However, most of the time users do have a python solution submitted.

Selecting Python Language on LeetCode

You may select python or python3 languages from the drop-down in the Leetcode editor.

Official Python Solutions

It is difficult to find questions that have Python solutions. The official solutions might not have a python solution.

Using Editorial Tab

The official solution can be found in the Editorial tab. Along with the solution, you also get explanations and instructions, usually on several approaches to solving the problem.

Also, there is a discussion below the solution where you can comment on the solution but without posting your own solution. That is reserved for the Solutions tab.

Using Solutions Tab

The “Solutions” tab will have the user-submitted solutions, so try to find the python solutions there if there’s no official Python solution under the “Editorial” tab.

LeetCode Contests for Data Science

The last place to practice python as a data scientist is to use LeetCode contests. These are typically for software engineers. To pass the test cases, you need to be able to code well and fast. You need to solve all four questions during the contest within the given time limit.

But is it helpful for data scientists? Will it help you in your data science interviews? Think about different ways to improve your modeling and data analysis skills. Some people say it doesn’t provide the interview environment. In order to be a good data scientist, you don't need to solve brain teasers quickly but program well.

To begin the test, you just need to register but to win the contest, you have to obtain the highest score with the fastest finish time with no mistakes.

Alternatives: A Data Science SQL and Python Resource Specifically Designed for Data Scientists

One alternative to LeetCode that was built specifically for data scientists is StrataScratch. StrataScratch was designed to offer interview questions that test data science concepts. Not only is it important to understand how to manipulate the data but it’s important to implement solutions that compensate for real-life scenarios and edge cases.

StrataScratch has over 500+ real questions from real companies that can help you prepare for the coding portion of your data science interviews.

StrataScratch Features for Your Data Science Interview

Here are some of the features that can help you in your data science interviews and your daily job as a data scientist.

Both SQL and Python Solutions for Each Data Science Question

SQL and Python have become popular languages for data science these days. In most data science interviews, you are allowed to use any language to showcase your skills. And StrataScratch allows you to learn and solve every data science question in both Python and SQL coding languages.

Real Data Science Questions From Real Companies

On StrataScratch, you have the ability to filter by the company. You have the ability to analyse the different types of data from company-to-company and industry-to-industry.

Video Solutions

Learning through the video content is the best way for this generation and StrataScratch provides over 50 video solutions on the platform to help you prepare for your data science interview.

Explore Other User’s Solutions and Learn the Alternative Approaches

StrataScratch provides you with the ability to explore other user's solutions. This helps you in learning alternative approaches.

You can also discuss and ask about any data science question on the platform. The StrataScratch community is always there to answer your questions. So you don't have help from only other users but also from the StrataScratch team.

Also, check out our post on LeetCode vs HackerRank vs StrataScratch for Data Science where we compared these three platforms.​

Conclusion

We hope you've learned something from the above tips that you can apply to your next technical interview. LeetCode provides a huge place for practicing real interview questions, but it's designed for software developers and provides algorithm-based questions to practice. However, there is no need to worry as we have many alternative ways to practice Python questions for data science, and StrataScratch is one of them.