Java program to compute the factorial of given number

Program Description

Write a java program to compute the factorial of a given number.

IPO Chart

Input

We will take input from the user for the given number. Let’s call this number n.

Process 

Compute n!

n! = (n)*(n-1)*(n-2)*…… * 1 

Output

The program will output n! for the given n number.

 

Java Program

import java.util.Scanner;

/**************************************************
 * FactorialNumber.java
 * @program : Factorial of n 
 * @web : www.TestingDocs.com
 * @version : 1.0
 **************************************************/

public class FactorialNumber { 
 public static void main(String args[]){
 int i,fact; 
 Scanner keyboard= new Scanner(System.in);
 System.out.println("Enter n : ="); 
 int number= keyboard.nextInt();//It is the number to calculate factorial 
 // positive number part
 if(number>= 0) {
 fact=1;
 for(i=1;i<=number;i++){
 fact=fact*i; 
 }
 }
 //negative number part
 else {
 fact=1;
 for(i=1;i<=-number;i++){
 fact=fact*i; 
 }
 fact = fact*-1;
 }
 System.out.println("Factorial of "+number+" is: "+fact);

 } 
}

 

 

Program Output

Enter n : =
5
Factorial of 5 is: 120

Screenshot

 

Factorial program using Recursion:

https://www.testingdocs.com/questions/factorial-java-program-using-recursion/