Factorial of a given number – Algorithm, Flowchart, and Program

What is the factorial of a number?

Factorial is a product of all positive integers less than or equal to a given number n. Factorial is denoted by a symbol (!).  In simple language, factorial is multiplying the whole numbers until 1.

for example,

Factorial of 5! = 5x4x3x2x1 = 120

In this way, we can calculate the factorial of any positive integer number.

In programming, you have to write an algorithm and program to calculate the factorial of a given number. Finding a factorial of a number is one of the most common programs to ask in the interview. The interviewer asks about the factorial program to check your basic programming knowledge and how you apply the logic to solve it.

So you must understand the flowchart and program of the factorial of a number.

Below I have given a flowchart, algorithm, and program to calculate the factorial of a given number.

Also Read: Check if number is Palindrome – Algorithm, Flowchart and Program

Flowchart for factorial of a number

Algorithm for finding the factorial of a number

Step 1: Start

Step 2: Read the input number from the user

Step 2: Declare and initialize variables fact = 1 and i =  1

Step 4:  Repeat the loop until  i<=num

–  fact = fact * i

–  i =  i++

Step 5:  Print fact to get the factorial of a given number

Step 6: Stop

Also Read: Bubble sort algorithm in java

Factorial of a given number in Java

import java.util.Scanner;

class Factorial {

	public static void main(String[] args){
	
	Scanner sc = new Scanner(System.in);
		System.out.println("Enter Number: ");
		int num = sc.nextInt();
		
		int fact = 1;
		
		for(int i=1; i<=num; i++){
		
			fact = fact * i;
			
		}
		
		System.out.println("Factorial of a given number is " + fact);
		
		}
		
	}