// Example illustrating that when you modify 
// a Java String you get a new String 
// Of course! this is true, because Java strings are immutable!
//
// StringBuffers are not immutable, however

public class str 
{
   public static void main(String[] args)
   {
       java.util.Scanner s = new java.util.Scanner (System.in);
       String u = s.nextLine();
       String v = u;
       System.out.println( u==v);         // True
       u = u + s.nextLine();
       System.out.println( u==v);         // False
       System.out.println( u.equals(v));  // False
       System.out.println();

       StringBuffer b = new StringBuffer(u);
       StringBuffer c = b;
       System.out.println( b==c);         // True
       System.out.println( b.equals(c));  // True
       b.reverse();
       System.out.println( b==c);         // True
       System.out.println( b.equals(c));  // True
   }

}