package Maths; //change around 'n' for different factorial results public class Factorial { public static void main(String[] args) { int n = 5; System.out.println(n + "! = " + factorial(n)); } //Factorial = n! = n1 * (n-1) * (n-2)*...1 /** * Calculate factorial N * * @param n the number * @return the factorial of {@code n} */ public static long factorial(int n) { if (n < 0) { throw new ArithmeticException("n < 0"); //Dont work with less than 0 } long fac = 1; for (int i = 1; i <= n; ++i) { fac *= i; } return fac; //Return factorial } }