#includeIn this example, a window with two buttons is created using the Surface library. The `Surface::Window` class represents the main window, while the `Surface::Button` provides a clickable button that can be added to the window. The `window.AddControl()` function is used to add the buttons to the window, and `Surface::Run()` is called to start the GUI event loop. The Surface library is part of the FLTK (Fast Light Toolkit) package, which is an open source C++ GUI development toolkit that provides a similar set of features to other popular GUI toolkits like Qt and wxWidgets.// Define a window and some buttons Surface::Window window("My GUI", 800, 600); Surface::Button button1("Button 1", 100, 100, 80, 30); Surface::Button button2("Button 2", 200, 100, 80, 30); // Add the buttons to the window window.AddControl(button1); window.AddControl(button2); // Run the program Surface::Run();