import java.awt.Button;
import java.awt.Frame;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;


public class Okno2 extends Frame implements ActionListener{
	Button gumbi[] = new Button[4];
	public Okno2(){
		this.setSize(500, 400);
		this.setLayout(new GridLayout(2, 2));
		for(int i = 0; i < 4; i++){
			gumbi[i] = new Button("1");
			gumbi[i].addActionListener(this);
			add(gumbi[i]);
		}
		this.setVisible(true);
	}
	/**
	 * @param args
	 */
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Okno2 oo = new Okno2();
	}
	public void actionPerformed(ActionEvent arg0) {
		// TODO Auto-generated method stub
		for(int i = 0; i < 4; i++){
			if(arg0.getSource() == gumbi[i]){
				gumbi[i].setLabel(gumbi[i].getLabel() + "1");
			}
		}
	}

}