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[Benjamin SCHWARZ <>]

Hello,

  I am currently reading an old code and find some dubious lines. Can
you please tell me if my Union Find utilisation is correct ?

------------------------
typedef CGAL::Union_find< Cell_handle > UnionFindForCellHandle;
        UnionFindForCellHandle uf;

        // Bootstrap : every pocket cell is a singletton
        for (j = cells.begin(); j!=cells.end();j++) {
                if ((*j)->info().getPocketNumber() != -1) {
                        uf.make_set(*j);
                        };
                };

        // doube rambling and merge touching cells
        UnionFindForCellHandle::iterator u,v;
        int idx;
        for (u = uf.begin(); u != uf.end(); u++) {
                for (v = uf.begin(); v != u; v++) {
------------------------

In the last line of this code sample : 
  "for (v = uf.begin(); v != u;"
I postulated that iterators u and v will trasverse the union find
structure in the same sequence, so that I can stop v on the "diagonal"
and avoid symetrical stuff. And the thing seems to run OK... Is this a
trustable feature of union find iterators or is this a side efect of the
actual implementation ?

   --Ben