#include <QtGui>
#include <QApplication>
#include <QtWidgets>

int main(int argc, char * argv[])
{
    QApplication app(argc, argv);

    QWidget window;
    window.resize(600, 600);
    window.show();
    window.setWindowTitle("My Qt Application!");

    QPushButton * button = new QPushButton("Press me", &window);
    button->move(100, 100);
    button->show();

    return app.exec();
}