Sorting a qLinkedList

[pwaldron]

Is it possible to sort a qLinkedList structure? The qLinkedList doesn't seem to have random access iterators, so the compiler complains when I try and pass the linked list to the sorting function. Simple code is shown below; if the qLinkedList is changed to qList then everything is fine, but my application needs iterators to remain valid after sorting, so qList/qVector aren't suitable.



#include <QtCore/QCoreApplication>
#include <QLinkedList>
#include <QtAlgorithms>

int main(int argc, char *argv[])
{
QCoreApplication a(argc, argv);

QLinkedList<int> list;
list << 5 << 2 << 7 << 12;
qSort (list.begin, list.end());

return a.exec();
}


Any ideas?

EDIT: It looks like the problem may be a relatively recent one. In Qt 4.1 qSort only required bidirectional iterators, which qLinkedList would support. In Qt 4.6 the requirement has been bumped up to random access iterators.

[wysota]

Did you try using std::sort()?

[pwaldron]

Same problem. std::sort requires a random access iterator, not a bidirectional one.

[wysota]

Both std::sort and qSort implement QuickSort and this one indeed needs a random access iterator. You can try doing bubble sort or insert sort, this should work on iterators with more restrictions.