package Maths;

public class FactorialRecursion {

/* Driver Code */

public static void main(String[] args) {

assert factorial(0) == 1;

assert factorial(1) == 1;

assert factorial(2) == 2;

assert factorial(3) == 6;

assert factorial(5) == 120;

}

/**

* Recursive FactorialRecursion Method

*

* @param n The number to factorial

* @return The factorial of the number

*/

public static long factorial(int n) {

if (n < 0) {

throw new IllegalArgumentException("number is negative");

}

return n == 0 || n == 1 ? 1 : n * factorial(n - 1);

}

}