import java.awt.*;
import java.awt.event.*;
import java.applet.*;

public class Applet1 extends Applet {
  private boolean isStandalone = false;
  private TextField nField = new TextField();
  private TextField kField = new TextField();
  private Button probbutton = new Button();
  private TextField rField = new TextField();
  private Label label1 = new Label();
  private Label label2 = new Label();
  private Label label3 = new Label();
  //引数値の取得
  public String getParameter(String key, String def) {
    return isStandalone ? System.getProperty(key, def) :
      (getParameter(key) != null ? getParameter(key) : def);
  }

  //アプレットのビルド
  public Applet1() {
  }
  //アプレットの初期化
  public void init() {
    try {
      jbInit();
    }
    catch(Exception e) {
      e.printStackTrace();
    }
  }
  //コンポーネントの初期化
  private void jbInit() throws Exception {
    nField.setText("5");
    nField.setBounds(new Rectangle(64, 43, 62, 25));
    this.setLayout(null);
    kField.setBounds(new Rectangle(194, 44, 67, 25));
    kField.setText("3");
    probbutton.setLabel("計算");
    probbutton.setBounds(new Rectangle(55, 87, 79, 24));
    probbutton.addActionListener(new java.awt.event.ActionListener() {
      public void actionPerformed(ActionEvent e) {
        probbutton_actionPerformed(e);
      }
    });
    rField.setText("0");
    rField.setBounds(new Rectangle(177, 124, 83, 26));
    label1.setText("n");
    label1.setBounds(new Rectangle(35, 47, 17, 16));
    label2.setText("k");
    label2.setBounds(new Rectangle(161, 49, 22, 16));
    label3.setText("ｎ回投げてk回成功");
    label3.setBounds(new Rectangle(168, 88, 114, 30));
    this.add(kField, null);
    this.add(nField, null);
    this.add(label1, null);
    this.add(label2, null);
    this.add(probbutton, null);
    this.add(rField, null);
    this.add(label3, null);
  }
  //アプレットの情報取得
  public String getAppletInfo() {
    return "アプレット情報";
  }
  //引数情報の取得
  public String[][] getParameterInfo() {
    return null;
  }

  void probbutton_actionPerformed(ActionEvent e) {
    int nnum=Integer.parseInt(nField.getText());
    int knum=Integer.parseInt(kField.getText());
    double prob=0.0;
    int cb=comb(nnum,knum);
    prob=cb*Math.pow(5.0,nnum-knum)/Math.pow(6.0,nnum);
    System.out.println("nCk:"+cb);
    rField.setText(Double.toString(prob));
  }

  int fact(int num){
    int rs=1;
    for (int i=1;i<=num;i++){
      rs = rs*i;
    }
    return rs;
  }

  int comb(int nnum,int knum) {
    int rs=1;
    for (int i=nnum;i>nnum-knum;i--){
      rs = rs*i;
    }
    return rs/fact(knum);
  }

}