Keyboard

import java.io.*;
class Keyboard{

  public static String readLine(){
    try {
      BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
      return (in.readLine());
    } catch(Exception e) {
      return ("");
    }
  }

  public static double readDouble(){
    double enter = Double.parseDouble(readLine());
    return (enter);
  }

  public static char readChar(){
    char ch =  readLine().charAt(0);
    return (ch);
  }

  public static void writeLine(String value){
    System.out.println(value);
  }

  public static void writeLine(Double value){
    System.out.println(value);
  }


}