Question

What will the following code display? \\[\begin{array}{l}\text { numbers } 1=[1,2,3] \\ \text { numbers } 2=[10,20,30] \\\\\text { numbers } 3=\text { numbers } 1+\text { numbers } 2\end{array}\\] print (numbers1) print (numbers 2 ) print (numbers3)

Short answer

- print(numbers1) - print(numbers2) - print(numbers3) Answer: The outputs of the print statements are: - [1, 2, 3] - [10, 20, 30] - [1, 2, 3, 10, 20, 30]

Step-by-step solution

Define 'numbers1' list

The first line of code defines the list 'numbers1' with elements 1, 2, and 3. So, numbers1 = [1, 2, 3].

Define 'numbers2' list

The second line of code defines the list 'numbers2' with elements 10, 20, and 30. So, numbers2 = [10, 20, 30].

Define 'numbers3' list by concatenating 'numbers1' and 'numbers2'

The third line of code defines the list 'numbers3' by concatenating the lists 'numbers1' and 'numbers2'. This means that all the elements of 'numbers2' will be appended to the list 'numbers1'. So, numbers3 = numbers1 + numbers2 = [1, 2, 3] + [10, 20, 30] = [1, 2, 3, 10, 20, 30].

Print the lists

We have three print statements. Each of them will print one list, i.e: - print(numbers1) will display [1, 2, 3]. - print(numbers2) will display [10, 20, 30]. - print(numbers3) will display [1, 2, 3, 10, 20, 30]. So, the final output of the given code will be: [1, 2, 3] [10, 20, 30] [1, 2, 3, 10, 20, 30]

Key concepts

Python Programming

Python is a versatile and widely-used programming language known for its readability and ease of use. It's often recommended for beginners due to its simple syntax that resembles natural language. Python is used in a variety of applications, from web development to data analysis and machine learning. It's object-oriented, meaning it organizes code into objects with properties and behaviors, and it supports multiple programming paradigms.

One of the basic yet powerful features of Python is its ability to manipulate lists. In the exercise provided, Python lists are used to store sequences of numbers. The code shows how to declare these lists and perform operations on them, specifically concatenation—joining lists end-to-end to create a new list. Understanding these fundamentals is critical for developing Python programming skills and moving on to more complex tasks.

List Operations in Python

Lists in Python represent ordered sequences of items. They are mutable, which means they can be modified after their creation. Common list operations include indexing to retrieve specific items, slicing to get subsets of a list, appending items to the end, inserting items at specific positions, and concatenating two or more lists.

In the step-by-step solution of the given exercise, concatenation is performed using the '+' operator. This operation does not change the original lists but instead creates a new list containing elements of both. The concept of concatenation is fundamental as it allows for the combination of data and is frequently used in data manipulation tasks. It’s important to note that the '+' operator when used on lists, differs from its use with numbers, where it performs addition, exemplifying operator overloading in Python.

Introduction to Python

Python was created by Guido van Rossum and released in 1991. It was designed with code readability in mind, aiming to allow programmers to express concepts in fewer lines of code. Python's syntax allows developers to write clear, logical code for small and large-scale projects.

Python's standard library is very comprehensive and can help perform a variety of tasks correlated with regular expressions, databases, web browsers, etc. For beginners, Python’s simplicity means that one can quickly start writing programs that actually do something, which is incredibly satisfying. For instance, the list operations demonstrated in the exercise are intuitive and encourage new learners to explore more complex structures and algorithms in Python, thereby gradually elevating their programming skills.