How to Write a Python Program to Accept User Input and Calculate Factorials or Print Multiplication Tables

In this guide, we will walk you through the process of creating a Python program that can either calculate the factorial of a number if it is less than 10, or print the multiplication table of a number if it is greater than or equal to 10. This tutorial will cover the necessary steps and provide sample code snippets to help you achieve your goal.

Step-by-Step Guide

The first step is to prompt the user to enter a number. Python allows for easy user input handling using the built-in `input` function. Here is a detailed breakdown of the process:

1. Accepting User Input

Use the input() function to receive the number from the user. The input is initially a string, so convert it to an integer using the int() function.

number  int(input("Enter a number: "))

2. Condition Check

Next, check if the number is less than 10. If it is, proceed to calculate its factorial. If the number is 10 or more, print its multiplication table.

2.1. Calculating Factorial

If the number is less than 10, use the math.factorial() function to calculate the factorial. The math module provides several mathematical functions, including the calculation of factorials.

import math
factorial  math.factorial(number)
print("Factorial of", number, "is", factorial)

2.2. Printing Multiplication Table

For numbers 10 or greater, print the multiplication table from 1 to 10. This can be achieved using a loop to multiply the number by each integer from 1 to 10 and then print the results.

for i in range(1, 11):
    print(f"{number} x {i}  {number * i}")

The full code for this program can be written as follows:

import math
# Get user input
number  int(input("Enter a number: "))
# Check if the number is less than 10
if number 

Optimizing the Code with Functions

To make the program cleaner and more modular, it is a good practice to break down the tasks into smaller functions. Here is how you can refactor the code:

3.1. Getting User Input with Validation

Create a function to handle user input, ensuring that the input is a valid integer.

def get_integer(prompt):
    while True:
        try:
            return int(input(prompt))
        except ValueError:
            print("Invalid input. Please enter a valid integer.")

3.2. Calculating Factorial

Create a function to calculate the factorial of a number.

def factorial(n):
    f  1
    for i in range(2, n   1):
        f * i
    return f

3.3. Printing Multiplication Table

Create a function to print the multiplication table of a number.

def print_multiplication_table(n):
    print(f"Multiplication table of {n}")
    for i in range(1, 11):
        print(f"{n} x {i}  {n * i}")

3.4. Main Function

The main function will call the other functions to get the input, perform the necessary operations, and print the results.

def main():
    n  get_integer("Enter a number: ")
    if n 

The final program is now easier to read and maintain. It separates the concerns of input handling, factorial calculation, and output printing into smaller, reusable functions.

Additional Considerations

When writing and testing your Python program, ensure you include error handling to manage invalid inputs gracefully. By catching and handling potential errors, such as when the user enters a non-integer value, you can improve the robustness of your program.

By following these steps, you will have a Python program that can either calculate the factorial of a number (if it is less than 10) or print its multiplication table (if it is 10 or greater).

Related Topics

Python programming - Learn more about the language and its capabilities. Factorial calculation - Explore more about the mathematical concept and its applications. Multiplication table - Understand the importance of multiplication tables in mathematics.