Java – Find Factorial of A Given Number

Write a Java program to find a factorial of the given number input by the user.

What is Factorial of Number?

The factorial is represented by the exclamation mark (!). A simple formula to calculate the factorial of a number is

n! = n (n - 1)!

For an example, the factorial of 5 is equivalent to 5 x 4 x 3 x 2 x 1.

Java Program to Find Factorial of a Number

This is a Java program to find the factorial of a Number using for loop. This program prompt user to enter a number and calculate factorial of that number. Then print the factorial of the number.

import java.util.Scanner;
public class FindFactorial {
  private static Scanner scanner = new Scanner( System.in );

  public static void main(String[] args) {

    System.out.println("Enter a number: ");
    String input = scanner.nextLine();
    int num = Integer.parseInt( input );
    int fact = 1;

    for (int i = 1; i <= num; i++)
    {
       fact = fact * i;
    }
		
    System.out.println("The factorial of " + num + " is " + fact);
  }
}

import java.util.Scanner;

public class FindFactorial {

private static Scanner scanner = new Scanner( System.in );

public static void main(String[] args) {

System.out.println("Enter a number: ");

String input = scanner.nextLine();

int num = Integer.parseInt( input );

int fact = 1;

for (int i = 1; i <= num; i++)

{

fact = fact * i;

}

System.out.println("The factorial of " + num + " is " + fact);

}

Compile and run program:

javac FindFactorial.java
java FindFactorial

Result:

Enter a number:
5
The factorial of 5 is 120