Computing Factorial in Java

Factorial of a positive integer n is multiplication of all positive integers from n till 1. Factorial is written as n!.

5! = 5 x 4 x 3 x 2 x 1 = 120

Factorial of zero is considered as 1

Finding Factorial using a loop

package com.techstackjournal.java.basics;

public class FactorialNumberExample1 {
	public static void main(String[] args) {
		int n = 3;
		int factorial = factorial(n);
		System.out.println("Factorial of " + n + " is " + factorial);
	}
	private static int factorial(int n) {
		int factorial = 1;
		for (int i = 1; i <= n; i++) {
			factorial = factorial * i;
		}
		return factorial;
	}
}

Finding Factorial using Recursive Function

package com.techstackjournal.java.basics;
public class FactorialNumberExample2 {
	public static void main(String[] args) {
		int n = 3;
		int factorial = factorial(n);
		System.out.println("Factorial of " + n + " is " + factorial);
	}
	private static int factorial(int n) {
		if (n == 0) {
			return 1;
		} else {
			return n * factorial(n - 1);
		}
	}
}

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