import javax.swing.*;
import java.awt.event.*;
import java.awt.*;


public class o2 extends JFrame{
	JTextField input = new JTextField(25);
	String tmp, wTemp;
	int count=0;
	o2(){
		super("Calculator");
		setLayout(new BorderLayout());
		add(input, BorderLayout.NORTH);
		input.setHorizontalAlignment(JTextField.RIGHT);
		JPanel numbs = new JPanel(new GridLayout(4,3));
		add(numbs);
		for (int x=1;x<10;x++){
			JButton tmpBut = new JButton(""+x);
			numbs.add(tmpBut);
			tmpBut.addActionListener(new NumButton());
		}
		JButton clear = new JButton("*");
		numbs.add(clear);
		clear.addActionListener(new ClearButton());
		JButton zero = new JButton("0");
		numbs.add(zero);
		zero.addActionListener(new NumButton());
		JButton staket = new JButton("#");
		numbs.add(staket);
			
		setSize(360,200);
		setVisible(true);
	}
	class NumButton implements ActionListener{
		public void actionPerformed(ActionEvent ave){
			String sTemp = ((JButton)ave.getSource()).getText();
			if (count>0){
				wTemp=tmp+sTemp;
				input.setText(wTemp);
			}else{
				input.setText(sTemp);
				count++;
				wTemp=sTemp;
			}
			tmp=wTemp;			
		}
	}
	class ClearButton implements ActionListener{
		public void actionPerformed(ActionEvent ave){
			input.setText("");
			tmp=null;
			count=0;
		}
	}
	
	public static void main(String[]args){
		new o2();
	}
}