CONTROL STRUCTURES II: REPETITION - Java Programming: From Problem Analysis to Program Design - page 276

while (counter <= nthFibonacci)
{

current = previous2 + previous1;
previous1 = previous2;
previous2 = current;
counter++;

}

9. Append the nth Fibonacci number to outputString . Notice that
the nth Fibonacci number is stored in current .
10. Display the output dialog box showing the first two and the nth Fibonacci
numbers.

COMPLETE PROGRAM LISTING
//*************************************************************
// Author: D.S. Malik
//
// Program: nth Fibonacci number
// Given the first two numbers of a Fibonacci sequence, this
// determines and outputs the desired number of the Fibonacci
// sequence.
//*************************************************************
import javax.swing.JOptionPane;

public class FibonacciNumber
{

public static void main (String[] args)
{

//Declare variables

String inputString;
String outputString;

int previous1;

int previous2;

int current = 0;

int counter;

int nthFibonacci;

inputString =
JOptionPane.showInputDialog("Enter the first "
+ "Fibonacci number: "); //Step 1

previous1 = Integer.parseInt(inputString); //Step 2

inputString =
JOptionPane.showInputDialog("Enter the second "
+ "Fibonacci number: "); //Step 3
previous2 = Integer.parseInt(inputString); //Step 4