static QWidgetMapper *mapper;
    static QWidgetSet *uncreatedWidgets;

typedef QHash<WId, QWidget *> QWidgetMapper;
typedef QSet<QWidget *> QWidgetSet;

#include <QApplication>
#include <QHBoxLayout>
#include <QSlider>
#include <QSpinBox>

int main(int argc, char *argvp[])
{
QApplication app(argc,argv);
QWidget *window = new QWidget;
window->setWindowTitle("enter your age");
QSpinBox *spinBox = new QSpinBox;
QSlider    *slider = new QSlider(Qt::Horizontal);
spinBox->setRange(0,130);
slider->setRange(0,130);
QObject::connect(spinBox, SIGNAL(valueChanged(int)), slider, SLOT(setValue(int)));
QObject::connect(slider, SIGNAL(valueChanged(int)), spinBox, SLOT(setValue(int)));
spinBox->setValue(35);
QHBoxLayout *layout = new QHBoxLayout;
layout->addWidget(spinBox);
layout->addWidget(slider);
window->setLayout(layout);
window->show();
return app.exec();
}