#include < QFile >
#include < QTextStream >
 
 static void process_line(const QByteArray &)
 {
 }
 
 static void process_line(const QString &)
 {
 }
 
 int main()
 {
     QFile file("in.txt");
     if (!file.open(QIODevice::ReadOnly | QIODevice::Text))
         return 1;
 
     QTextStream in(&file);
     while (!in.atEnd()) {
         QString line = in.readLine();
         process_line(line);
     }
 }