Example of a Vehicle Routing Problem with Uninterruptible Breaks

[pmateusz]

An example of the Vehicle Routing Problem with Time Windows and Breaks. All breaks are mandatory and must be performed without interruptions. Since breaks without interruptions are not available off-the-shelf a custom constraint is developed. A warning message is printed every time vehicle's break overlaps with a visit.

Workaround for the issue: #569

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[pmateusz]

I have signed it!

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CLAs look good, thanks!

[Mizux]

Hi,

It seems "break" feature has been fixed internally, so I hope for v6.9 to bump routing library to our current internal code...

BTW I still keep this PR "open" until break is updated and this PR become obsolete.

[pmateusz]

So it was a bug indeed. Thank you for confirmation! I am pleased that the work I did helped a little. It is of course always better to fix the root cause rather than rely on the workaround my PR provides. Feel free to close the PR once it is best.

[tomika]

Dear Mateusz,
I would like to know if it is really necessary to add

solver()->AddConstraint(solver()->MakeIntervalVarRelation(current_interval, Solver::STARTS_AFTER_END, last_interval));

constraints?
Is it not a basic, already existing constraint in the whole routing calculation?
Thanks for your answer in advance.