package binarysearch;
import java.util.*;
import java.io.*;
public class BinarySearch {

  public static void main(String[] args) {
    int i;

    LinkedList list = new LinkedList();
    // Create a list of students, together with their room numbers.
    list.add(new Student("Fred Bloggs",10));
    list.add(new Student("Adam Smith",20));
    list.add(new Student("Gordon Bennett",31));
    list.add(new Student("Raquel Welsh",42));
    list.add(new Student("Meg Ryan",53));
    list.add(new Student("Julia Roberts",60));
    list.add(new Student("Dopy",7));
    list.add(new Student("Sleepy",8));
    list.add(new Student("Snow White",9));

    // Sort the list
    Collections.sort(list);
    // Create a temporary student with no name, just room 42
    // (since the compareTo method is only looking at the room number)...
    Student s = new Student("  ",42);
    // get the index of who is staying at room 42
    i = Collections.binarySearch(list,s);
    // and retrieve the student from the list
    Student who = (Student) list.get(i);
    // Print out who is actually staying at room 42
    System.out.println("The student staying in room 42 is :"+who.getName());
  }
}

class Student implements Comparable{
  private int roomNumber;
  private String name;
  public Student(String name, int roomNumber) {
    this.roomNumber = roomNumber;
    this.name = name;
  }

  public String getName() {
    return name;
  }
  public int getRoom() {
    return roomNumber;
  }
  public int compareTo(Object o) {
    Student s = (Student) o;
    if(s.roomNumber < roomNumber) {
      return 1;
    } else if (s.roomNumber == roomNumber) {
      return 0;
    } else {
      return -1;
    }
  }
}