Java Program to find Factorial of a Number

Posted in Java Tutorial

Updated on Oct 30, 2024

By Mari Selvan

👁️ 119 - Views

⏳ 4 mins

💬 1 Comment

Java Program to find Factorial of a Number

Photo Credit to CodeToFun

🙋 Introduction

In the world of programming, solving mathematical problems is a fundamental skill. One such mathematical operation is finding the factorial of a number.

The factorial of a non-negative integer is the product of all positive integers less than or equal to that number. It's denoted by the symbol !.

In this tutorial, we'll explore a Java program that efficiently calculates the factorial of a given number.

📄 Example

Let's take a look at the Java code that achieves this functionality.

Factorial.java

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public class Factorial {

// Function to calculate factorial
static long calculateFactorial(int num) {
  if (num == 0 || num == 1) {
    return 1;
  } else {
    return num * calculateFactorial(num - 1);
  }
}

// Driver program
public static void main(String[] args) {
  // Replace this value with your desired number
  int number = 5;

  // Call the function to calculate factorial
  long result = calculateFactorial(number);

  // Display the result
  System.out.println("Factorial of " + number + " is: " + result);
}
}

💻 Testing the Program

To test the program with a different number, replace the value of number in the main method.

Output

Factorial of 5 is: 120

Compile and run the program to see the factorial in action.

🧠 How the Program Works

The program defines a class Factorial containing a static method calculateFactorial that recursively calculates the factorial of a given number.
In the main method, replace the value of number with the desired input.
The program then calls the calculateFactorial method to compute the factorial.
The result is displayed using System.out.println.

🧐 Understanding the Concept of Factorial

Before delving into the code, let's take a moment to understand the concept of factorial.

The factorial of a non-negative integer n, denoted as n!, is the product of all positive integers less than or equal to n.

For example, the factorial of 5 (5!) is calculated as 5 × 4 × 3 × 2 × 1 = 120.

🎢 Optimizing the Program

While the provided program is effective, it uses recursion to calculate the factorial. Depending on the input value, this approach may lead to a stack overflow for large numbers. Consider exploring iterative solutions for larger inputs or optimizing the recursive approach.

Feel free to incorporate and modify this code as needed for your specific use case. Happy coding!