// Name:     Bradley Shedd
// Program:  Project#4
// Date:     November 16, 2010
// Class:    Java1302
// Filename: Fibo.java
// Purpose:  This class writes a recursive and an iterative function to
//           calculate the 40th element in a Fibonacci sequence. It also
//           times the process in milliseconds.

public class Fibo
{
    public static void main(String args[])
    {
      long start = System.currentTimeMillis();
      System.out.println("-----------------------------------------------" +
                         "-----------------------------------------------");
      System.out.println("The 40th element in this Fibonacci sequence using" +
                         " the recursive funtion is " + recursiveFib(40));
      long end = System.currentTimeMillis();
      System.out.println("The time past in milliseconds(msec) to return the " +
                         "element recursively is " + (end-start));
      start = System.currentTimeMillis();
      System.out.println("-----------------------------------------------" +
                         "-----------------------------------------------");
      System.out.println("The 40th element using the iterative function" +
                         " is " + iterativeFib(40));
      end = System.currentTimeMillis();
      System.out.println("The time past in msec to return the element " +
                         "iteratively is " + (end-start));
      System.out.println("===============================================" +
                         "===============================================");
      for
         (int i = 1; i <=40; i++)
      System.out.println(iterativeFib(i));
      System.out.println("===============================================" +
                         "===============================================");
     
    }




public static int recursiveFib(int n)
{
  if (n<2)
   return n;
 
  else
   return recursiveFib(n-1)+recursiveFib(n-2);

}
public static int iterativeFib(int n)
{
int i,x = 0, y = 1;
  if (n<2)
   return n;
 
 else
   for (i=1;i<n;i++)
   {
     y=x+y;
     x=y-x;
   }
  
   return y;
   }
}

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