20+ Jr Python Developer Interview Questions and Answers

Return the maximum number of unique candy types Alice can have after splitting equally with her brother and following the doctor's advice.

• Create a set of unique candy types

• Calculate the maximum number of candies Alice can have after splitting and following the doctor's advice

• Return the maximum number of unique candy types

I developed a proof of concept for a new feature by conducting research, creating a plan, implementing the feature, and testing it thoroughly.

• Researched the requirements and potential solutions for the new functionality

• Created a detailed plan outlining the steps needed to implement the feature

• Implemented the feature using Python programming language

• Tested the functionality thoroughly to ensure it met the requirements and was bug-free

Candidates should focus on Python fundamentals, libraries, problem-solving, and coding best practices for interviews.

• Understand Python basics: data types, control structures, and functions. Example: Know how to use lists, dictionaries, and loops.

• Familiarize yourself with popular libraries: NumPy, Pandas, and Flask. Example: Be able to manipulate data using Pandas.

• Practice coding problems on platforms like LeetCode or HackerRank. Example: Solve problems related to algorithms a...read more

Use a dictionary to keep track of elements and their counts, then return elements with count > 1.

• Create an empty dictionary to store elements and their counts.

• Iterate through the array and update the counts in the dictionary.

• Return elements with count > 1 as duplicates.

Check if nums can be divided into n pairs

• Sort the nums array

• Iterate through the array and check if each pair can be formed

• Return True if all pairs can be formed, otherwise return False

The number of operations required to make either num1 or num2 equal to 0 is the sum of num1 and num2.

• Add num1 and num2 to get the total number of operations required.

• In this case, num1 = 2 and num2 = 3, so the total number of operations required is 2 + 3 = 5.

I have 2 years of experience in Python development, working on web applications and data analysis projects.

• Developed web applications using Django framework

• Utilized Python for data analysis and visualization using libraries like Pandas and Matplotlib

• Experience with RESTful APIs and integrating third-party services

• Worked on automation scripts using Python

Lambda function is an anonymous function in Python. List is a collection of items. Append adds an element to a list, while extend adds elements from another list. Pandas is a Python library for data manipulation. CSV files can be read using pandas.

• Lambda function is a small anonymous function defined with the lambda keyword.

• List is a collection of items enclosed in square brackets, separated by commas.

• Append is used to add a single element to the end of a list.

• Extend is used ...read more

There are 7 types of operators in Python.

• Arithmetic operators (+, -, *, /, %, //, **)

• Comparison operators (==, !=, >, <, >=, <=)

• Assignment operators (=, +=, -=, *=, /=, %=, //=, **=)

• Logical operators (and, or, not)

• Bitwise operators (&, |, ^, ~, <<, >>)

• Identity operators (is, is not)

• Membership operators (in, not in)

Lambda function is an anonymous function that can be defined in a single line of code.

• Lambda functions are used for simple and concise operations.

• They can take any number of arguments but can only have one expression.

• They are often used as arguments for higher-order functions.

• Example: lambda x: x**2 defines a function that squares its input.

MySQL is a popular open-source relational database management system. HTML and CSS are markup and styling languages used for web development.

• MySQL is a database management system used to store and manage data in a structured format.

• HTML is a markup language used to create the structure of web pages.

• CSS is a styling language used to design the layout and appearance of web pages.

numpy is a Python library for numerical operations on arrays and matrices. JavaScript is a programming language for web development.

• numpy is used for mathematical and logical operations on arrays.

• It provides efficient and fast operations on large datasets.

• JavaScript is used for client-side and server-side web development.

• It allows interactive and dynamic features on websites.

• JavaScript can manipulate HTML elements and handle user interactions.

React JS is a popular JavaScript library for building user interfaces, particularly single-page applications, using reusable components.

• Component-based architecture: React allows developers to create reusable UI components, improving code maintainability.

• Virtual DOM: React uses a virtual representation of the DOM to optimize rendering and improve performance.

• State management: React components can manage their own state, allowing for dynamic and interactive user experiences.

• JS...read more

Python is a high-level programming language known for its simplicity, readability, and versatility. It is widely used for web development, data analysis, artificial intelligence, and more.

• Python is easy to learn and read, making it a great choice for beginners and experienced developers alike.

• Python has a large standard library and many third-party packages, making it suitable for a wide range of applications.

• Python is used in various fields such as web development (Django, F...read more

Lambda functions are anonymous functions that can be defined without a name.

• Lambda functions are defined using the lambda keyword.

• They can take any number of arguments, but can only have one expression.

• They are often used as arguments for higher-order functions.

• Example: lambda x: x**2 defines a lambda function that squares its input.

Multi threading is a programming concept where multiple threads within a process execute independently to improve performance.

• Allows for concurrent execution of tasks within a single process

• Can improve performance by utilizing multiple CPU cores

• Requires careful synchronization to avoid race conditions

• Example: Running a web server that can handle multiple client requests simultaneously

Tuple is an immutable data structure in Python that stores a collection of elements.

• Tuples are ordered and indexed collections of elements.

• They are defined using parentheses () and can contain elements of different data types.

• Tuples are immutable, meaning their elements cannot be changed once they are created.

• Example: my_tuple = (1, 'hello', 3.14)

In Python, comments are used to explain code and are ignored during execution.

• Single-line comments start with a '#' symbol. Example: # This is a comment

• Multi-line comments can be created using triple quotes. Example: ''' This is a multi-line comment '''

• Comments can be used to temporarily disable code. Example: # print('This will not run')

• Use comments to clarify complex logic or algorithms for better readability.

Numpy is a Python library for numerical computing with support for large, multi-dimensional arrays and matrices.

• Numpy provides efficient mathematical operations on arrays.

• It is widely used in scientific computing, data analysis, and machine learning.

• Numpy arrays are homogeneous and can be indexed and sliced like lists.

• Broadcasting allows for element-wise operations on arrays of different shapes.

• Numpy also includes linear algebra, Fourier transform, and random number functions...read more

Pandas is a Python library used for data manipulation and analysis.

• Pandas provides data structures for efficiently storing and manipulating large datasets.

• It offers tools for data cleaning, merging, reshaping, and visualization.

• Pandas can handle various data formats such as CSV, Excel, SQL databases, and JSON.

• It is widely used in data science, finance, economics, and other fields.

• Example: df = pd.read_csv('data.csv') creates a pandas DataFrame from a CSV file.

Inheritance is a mechanism in object-oriented programming where a new class is created from an existing class.

• Allows for code reuse and avoids redundancy

• The new class (subclass) inherits properties and methods from the existing class (superclass)

• Subclass can add new properties and methods or override existing ones

• Example: A Car class can inherit properties and methods from a Vehicle class

Dict is a built-in data type in Python used to store key-value pairs.

• Dict functions include keys(), values(), items(), get(), pop(), update(), clear().

• Example: dict.keys() returns a list of all keys in the dictionary.

• Example: dict.get('key') returns the value associated with 'key'.

List is mutable, tuple is immutable in Python.

• List can be modified (add, remove, change elements), tuple cannot be modified.

• List is defined using square brackets [], tuple is defined using parentheses ().

• List is used when we have a collection of items that may need to be changed, tuple is used when we have a collection of items that should not change.

To start with Python, install it, set up an IDE, and write your first simple program.

• Download and install Python from the official website (python.org).

• Choose an Integrated Development Environment (IDE) like PyCharm, VSCode, or Jupyter Notebook.

• Write your first Python program: print('Hello, World!')

• Learn basic syntax: variables, data types, loops, and functions.

• Explore Python libraries like NumPy and Pandas for data manipulation.

Python can be run in various environments, including command line, IDEs, and online interpreters.

• Using the command line: Type 'python script.py' to run a Python script.

• Using an IDE: Open the script in an IDE like PyCharm or VSCode and click 'Run'.

• Using an online interpreter: Visit sites like Repl.it or Jupyter Notebook to run Python code directly in the browser.

• Interactive mode: Type 'python' in the command line to enter the interactive shell for immediate code execution.

Python comments are annotations in code that are ignored during execution, used for documentation and clarification.

• Single-line comments start with a '#' symbol. Example: # This is a comment

• Multi-line comments can be created using triple quotes. Example: ''' This is a multi-line comment '''

• Comments help improve code readability and maintainability.

• They are useful for explaining complex logic or providing context for future developers.

To find the 3rd largest element in an array, we can sort the array and select the appropriate index.

• Sort the array in descending order and select the element at index 2.

• Example: For array [5, 3, 8, 1, 2], sorted array is [8, 5, 3, 2, 1]. 3rd largest is 3.

• Alternatively, use a set to remove duplicates and then sort.

• Example: For array [5, 5, 3, 8, 1], unique sorted array is [8, 5, 3, 1]. 3rd largest is 3.