import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;

public class Pierwiastek extends HttpServlet {
	@Override
    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
		String xstr = request.getParameter("x");
		double x = 0;
		if (xstr != null) x = Double.parseDouble(xstr);
        response.setContentType("text/html");
        PrintWriter out = response.getWriter();
        String message = String.format("sqrt(%1$.1f) = %2$f", x, Math.sqrt(x));
        out.println("<h1>" + message + "</h1>");
    }
	@Override
    public void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
		doGet(request, response);
    }
}