Recursive Function: Factorial: Part 2: Java

Doing Factorial in Java

/*  * Factorial returns the factorial n!  * 2012.12.19  * Tetsuro  */   public class Factorial {          // constructor for Factorial class        public Factorial() {                      }          // this method returns n!        public int fact(int n) {               if (n == 0) {                      return 1;               }               else {                      return n * fact(n - 1);           // fact(n - 1) always returns 1               }        } }

public class RecursionTest {               /**         * Program for testing factorial object         */               public static void main(String[] args) {                             // instantiating f from Factorial class               // created object f               Factorial f = new Factorial();                             // run the factorial f with passing integer 5               // and print the result               System.out.print(f.fact(5));        } }

Example:

Factorial, “3!” works like this: