import java.io.*;
class Keyboard {
// Author: M. Dennis Mickunas, June 9, 1997
// Primitive Keyboard input of integers, reals,
// strings, and characters.
static boolean iseof = false;
static char c;
static int i;
static double d;
static String s;
/* WARNING: THE BUFFER VALUE IS SET TO 1 HERE TO OVERCOME
** A KNOWN BUG IN WIN95 (WITH JDK 1.1.3 ONWARDS)
*/
static BufferedReader input
= new BufferedReader (
new InputStreamReader(System.in),1);
public static int readInt () {
if (iseof) return 0;
System.out.flush();
try {
s = input.readLine();
}
catch (IOException e) {
System.exit(-1);
}
if (s==null) {
iseof=true;
return 0;
}
i = new Integer(s.trim()).intValue();
return i;
}
public static char readChar () {
if (iseof) return (char)0;
System.out.flush();
try {
i = input.read();
}
catch (IOException e) {
System.exit(-1);
}
if (i == -1) {
iseof=true;
return (char)0;
}
return (char)i;
}
public static double readDouble () {
if (iseof) return 0.0;
System.out.flush();
try {
s = input.readLine();
}
catch (IOException e) {
System.exit(-1);
}
if (s==null) {
iseof=true;
return 0.0;
}
d = new Double(s.trim()).doubleValue();
return d;
}
public static String readString () {
if (iseof) return null;
System.out.flush();
try {
s=input.readLine();
}
catch (IOException e) {
System.exit(-1);
}
if (s==null) {
iseof=true;
return null;
}
return s;
}
public static boolean eof () {
return iseof;
}
}