Create a Factorial Calculator

Author: phongus

18.3_FactorialCalculator/src/FactorialCalculator.java

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+/**
+ *  Fig. 18.3: FactorialCalculator
+ *  Recursive factorial method.
+ */
+public class FactorialCalculator
+{
+    //  recursive method factorial (assumes its parameter is >= 0)
+    public long factorial (long number)
+    {
+        if (number <= 1)
+            return 1;   //  test for base case
+        else
+            return number * factorial(number - 1);
+    }   //  end method factorial
+
+    //  output factorials for values 0-21
+    public static void main(String[] args)
+    {
+        //  calculate the factorials of 0 through 21
+        for (int counter = 0; counter <= 21; counter++)
+            System.out.printf("%d! = %d\n", counter, factorial(counter) );
+    }
+}