import java.util.Scanner;

public class Guesser {
    private int low;
    private int high;
    private Scanner keyboard;
    
    public Guesser() {
        this.low = 1;
        this.high = 100;
        this.keyboard = new Scanner(System.in);
    }
    
    public void guess() {
        int middle = (low + high) / 2;
        System.out.print("Is the number greater than " + middle + "? ");
        String answer = keyboard.nextLine();
        if(answer.charAt(0) == 'y' || answer.charAt(0) == 'Y') {
            low = middle + 1;
        } else {
            high = middle;
        }
    }

    public void run() {
        System.out.println("Think of a number between 1 and 100 and I'll guess it.");
        while(low < high) {
            guess();
        }
        System.out.println("The number is " + low + "!");
    }
    
    public static void main(String[] args) {
        Guesser engine = new Guesser();
        engine.run();
    }
}