Question

Write a program that reads in three integers and prints "in order" if they are sorted in ascending or descending order, or "not in order" otherwise. For example, \(\begin{array}{llll}1 & 2 & 5 & \text { in order } \\ 1 & 5 & 2 & \text { not in order } \\ 5 & 2 & 1 & \text { in order } \\ 1 & 2 & 2 & \text { in order }\end{array}\)

Short answer

Write a program that checks both non-decreasing (\(a \leq b \leq c\)) and non-increasing (\(a \geq b \geq c\)) conditions for three integers.

Step-by-step solution

Understand the Requirements

We need to create a program that takes three integers as input and determines if they are sorted in either ascending or descending order. If not, it should output "not in order". This includes checking for strictly increasing or decreasing sequences, as well as non-strict with equal numbers, like \(a \leq b \leq c\) or \(a \geq b \geq c\).

Plan the Logic

To solve the problem, the program will need to evaluate two conditions. First, check if the integers are in non-decreasing order (\(a \leq b \leq c\)). Second, check if they are in non-increasing order (\(a \geq b \geq c\)). If either condition is true, print "in order"; if neither is true, print "not in order".

Implement the Code

Write a program that reads three integers. Use conditional statements to check the sorted order. ```python # Read three integers a = int(input("Enter first number: ")) b = int(input("Enter second number: ")) c = int(input("Enter third number: ")) # Check if they are in order if (a <= b <= c) or (a >= b >= c): print("in order") else: print("not in order") ``` This program will first read three numbers from the user. Then, it will check both the non-decreasing and non-increasing conditions. Depending on the result, it will output either "in order" or "not in order".

Key concepts

Python Programming

Python is a versatile and powerful programming language, ideal for both beginners and experienced developers. One of its strengths lies in its clean and easy-to-read syntax.
This makes Python especially popular for developing web applications, data analysis tasks, and automating tasks.
Python uses indentation to define code blocks, which is one of the unique aspects of the language. Unlike other languages that use braces or keywords, Python’s indentation requirements allow for code to be naturally readable without losing structure clarity.
Python supports several programming paradigms, including procedural, object-oriented, and functional programming, which adds flexibility to how developers can write their programs.

• Procedural programming deals with writing procedures or methods that operate on data.
• Object-oriented programming focuses on creating objects that represent real-world entities.
• Functional programming is a programming paradigm where programs are constructed by applying and composing functions.

When developing in Python, a good practice is to make frequent use of comments to explain the code, which is especially helpful when working in teams or revisiting old projects. Python is also known for its extensive library support, offering modules and packages that make programming tasks easier across various domains.

Integer Comparison

Comparing integers in programming is a fundamental concept that involves evaluating conditions between two or more numbers. In Python, these comparisons are used extensively in conditional statements to determine the flow of a program.
Integer comparisons can involve different operations, such as:

• ==: Equal to. Checks if two integers have the same value.
• !=: Not equal to. Checks if two integers have different values.
• >: Greater than. Checks if one integer is larger than another.
• <: Less than. Checks if one integer is smaller than another.
• >=: Greater than or equal to. Checks if one integer is larger than or equal to another.
• <=: Less than or equal to. Checks if one integer is smaller than or equal to another.

In conditional statements, these operators help execute specific blocks of code depending on whether the comparison is true or false. For example, in the provided exercise, if (a <= b <= c) or (a >= b >= c): checks if three integers are in non-decreasing or non-increasing order, providing a straightforward way to determine whether a sequence is sorted.

User Input in Python

Handling user input is essential for creating interactive programs in Python. The input() function serves as the main tool for capturing user input from the console. This function reads data entered by the user, which is typically a string, and can be converted into other data types as necessary.
For example, when dealing with numbers, the int() function converts a string input into an integer, allowing for numerical operations like comparisons or arithmetic. In the exercise, user input is captured and immediately transformed to integers with int(input()), which streamlines the process of collecting numerical data.
Implementing user input involves several key steps:

• Prompting the user with a message, such as "Enter your age:" using the input() function.
• Storing the returned input into a variable.
• Converting the input into the applicable data type (e.g., integer, float) if needed.

When accepting user input, it is also a good practice to handle possible exceptions, ensuring the program does not crash due to unexpected data. This can be achieved using try-except blocks, which will gracefully catch and handle any input errors.