Code snippets from recursion lecture

Recursion.java

public class Recursion {

    public static class ExampleOne
    {
        public static void main (String args[])
        {
            count(0);
        }

        public static void count (int index)
        {
            System.out.println(index);
            if (index < 2)
                count(index+1);
        }
    }

    public static class ExampleTwo
    {
        public static void main (String args[])
        {
            upAndDown(1);
        }

        public static void upAndDown (int n)
        {
            System.out.print ("\nLevel-up: " +  n);
            if (n < 4)
                upAndDown (n+1);
            System.out.print ("\nLevel-down: " + n);
        }
    }

    public static class Factorial
    {
        public static void main (String args[])
        {
            for (int i = 1; i < 10; i++)
                System.out.println ( i + "! = " + findFactorial(i));
        }

        public static int findFactorial (int number)
        {
            if (number <= 1)
                return 1;
            else
                return number * findFactorial(number-1);
        }
    }

    public static class TailRecursion {

        public static void main (String args[])
        {
            printName(5);
        }

        public static void printName(int level){
            if( level <= 0 )
                return;
            System.out.println("Smith");
            printName(--level);
        }
    }


    public static class Fibonacci
    {
        public static void main (String args[])
        {
            int number = 5;
            long fibonacciValue = fibonacci( number );
            System.out.println (fibonacciValue);
        }

        public static long fibonacci( long n )
        {
            if ( n == 0 || n == 1 )
                return n;
            else
                return fibonacci( n - 1 ) + fibonacci( n - 2 );
        }


        static long [] array = new long [100];

        public static long memoizedFibonacci( long n )
        {
            if ( n == 0 || n == 1 )
                return n;
            else if (array[(int)n] != 0)
                return array[(int)n];
            else
            {
                array[(int)n] = fibonacci( n - 1 ) + fibonacci( n - 2 );
                return array[(int)n];
            }

        } // end method fibonacci

    }


}