Question

Write a program that reads in three strings and sorts them lexicographically. Enter a string: Charlie Enter a string: Able Enter a string: Baker Able Baker Charlie

Short answer

Read, store, sort, and print the strings in lexicographical order.

Step-by-step solution

Understand the Problem

The exercise requires you to take three strings as input and then sort them in dictionary order, which is known as lexicographical order. This means they should be sorted as if they were words in a dictionary.

Initialize Input

Start by creating a program that reads three strings from the user. In many programming languages, this can be done using functions like `input()` in Python.

Store the Strings

Store each of the input strings in separate variables for easy access. For instance, in Python, you might store them as `string1`, `string2`, and `string3`.

Sort the Strings

Use a sorting function available in your programming language to sort the list of collected strings. In Python, you can use the `sorted()` function or the `list.sort()` method to achieve this.

Print Sorted Strings

Finally, print the strings in their new, sorted order. Make sure you print each string on a new line to match the expected output format.

Key concepts

Lexicographical Order

When you think of lexicographical order, imagine how words are arranged in a dictionary. Lexicographical order sort strings based on the sequence of characters in the alphabet.
For example, the sequence we often think of is A-Z, so "Able" comes before "Baker" because "A" is before "B."
In Python, sorting strings lexicographically follows this natural order. If you have a list of strings, Python’s sorting algorithms look at the very first character, compare its position in the alphabet with other first characters, and arrange them accordingly.

• If the first characters are the same, they compare the second character, and so on till they find a difference.
• Strings are case-sensitive by default, meaning "apple" and "Apple" are treated differently.

Understanding lexicographical order is essential for managing string data effectively and allows for predictable and standardized sorting outputs.

Python Programming

Python is a versatile language perfect for handling tasks like string sorting, thanks to its straightforward syntax. In our exercise, we take advantage of Python’s simplicity to read and sort strings.
Python provides built-in functions and methods to work effortlessly with data types like strings. For instance, capturing user input in Python is as simple as using the `input()` function.
This makes it an ideal choice for beginners who are learning programming or handling strings for the first time. Additionally, variables in Python do not require explicit declaration, allowing you to focus more on the logic than on complex code structures.

• Dynamic typing allows you to store strings in variables without worrying about data types.
• Python’s extensive standard library provides powerful tools for sorting and other operations.

Python’s blend of simplicity and capability makes it an excellent language for learning and implementing basic programming concepts.

User Input Handling

Handling user input is a crucial part of making interactive programs. With Python, gathering input from the user is both simple and intuitive thanks to the `input()` function.
In the exercise, users are prompted to enter strings, which the program then processes. To handle input efficiently, you can read multiple input strings and store each in a variable.
This lets you manage individual inputs and decide how to process each one.

• Always consider what kind of input you expect from the user, and validate if necessary to enhance the program’s robustness.
• Prompt the user clearly so they understand what type of input is expected.

Using creative prompts or validations, you can make sure you get the right kind of input for processing and sorting.

Sorting Algorithms

Sorting algorithms are fundamental in computer science. They arrange data in a certain order to make searching and processing efficient.
In Python, sorting can be achieved using built-in functions and methods. The `sorted()` function returns a new sorted list from the elements of any iterable, while `list.sort()` sorts the list in place.
Both are flexible for automatically handling lexicographical sorting when applied to strings because of Python's native character order understanding.

• `sorted()` is useful when you need the original list to remain unchanged.
• `list.sort()` is more useful when you want to alter the original list directly.

These methods save you from implementing complex sorting algorithms manually, allowing you to focus more on application logic than on basic sorting operations.