java ---- Applet 计算第n个斐波那契序列数！

通过java Applet输出第n个斐波那契序列数！

编译工具eclipse +jdk

import java.applet.Applet;
import java.awt.Button;
import java.awt.Graphics;
import java.awt.Label;
import java.awt.TextField;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;


public class AppletInOut extends Applet implements ActionListener {
	Label prompt = new Label("输入要计算的第几个斐波那契序列数：");
	TextField input = new TextField(5);
	Button btn = new Button("计算");
	int n = 1;
	long fib = 0;
	public void init(){
		add(prompt);
		add(input);
		add(btn);
		btn.addActionListener(this);
	}

	public void paint(Graphics g){
		g.drawString("斐波那契序列第"+ n +"个数据是"+fib, 10, 50);
	}
	@Override
	public void actionPerformed(ActionEvent e) {
		// TODO Auto-generated method stub
		n = Integer.parseInt(input.getText());
		fib = Fibonacci(n);
		repaint();
	}
	long Fibonacci(int n){
	if(n==1||n==2)
		return n-1;
	else 
		return Fibonacci(n-1)+Fibonacci(n-2);
	//递归调用计算斐波那契数
}

}

程序运行效果：