Problematic activity

[Zsolt Udvari]

Hi all!

I'm working the next year's timetable in our school. I've input about half of activities (5. class to 10. class)  but fet can't generate the timetable. Everytime when I stop, says that can't place an activity (same activity in every case: "Id: 449, TN: CSMÁ, SN: Magyar,  StN: 10.D2, 10.D3"). I don't know why.
Can you help me?

(Please don't include to sample input files because this file isn't full)

[Volker Dirr]

it is impossible, because you didn''t care carefully about your courses.

activity:
10.D3
Informatika
MÓLÁ
Multimédia

and activity:
10.D1, 10.D2
Informatika
MÓLÁ
Számtech

can't be at the same time, because of the same teacher!

so there are only 2 solutions.
a) increase the number of hours per day (bad solution)
b) one of that activities (see above) must be teached by an other teacher.

[Zsolt Udvari]

Oh, you've right I thought that the class 10.D1 and 10.D2 are together (without 10.D3) on any other course, but no
Imho I'll make the follow: I'll erase one of these courses and I'll say the teacher that he should teach in 0. hour. We can't change the teacher because he is the chief of class.

One more question: how did you find these impossibility? The output of fet or you see the activities?

Thanks.
 Zsolt

[Liviu Lalescu]

Nice work, Volker :-)

[Volker Dirr]

One more question: how did you find these impossibility? The output of fet or you see the activities?

you told me, that the problem is at an activity in year 10.

so first of all i deleted all other years and generated again, just to know if this is only a problem of year 10 or a more complex problem.

but FET was still not able to find a solution. So it was clear that is a problem only of year 10.

then i increased the number of hours per day, generaed a timetable and view that timetable of year 10.
if you view that timetable you can see the problem very quick.

so i solved the problem in less then 5 minutes :-)

[Volker Dirr]

i forgot 2 more things:

there is also an 3 possible solition, but i fear it is not what you need.
If you swap subgroup 10.D2 into the other activity, then it is also solveable. I mean this:

activity:
10.D2, 10.D3
Informatika
MÓLÁ
Multimédia

and activity:
10.D1
Informatika
MÓLÁ
Számtech


and on other thing, not importned now, but maybe next year.
your samplefile will be a little bit sweeter if you don't call "2009-2010" as "year". Your years should be "5", "6", ...
it doesn't matter now, because your school is not so big and FET also understand your current version correct. But if your school grow a little bit more, your dataset will be more tidy if you do it like i suggested.

[Zsolt Udvari]

then i increased the number of hours per day, generaed a timetable and view that timetable of year 10.

Ohhh, very-very tricky Good to know this "trick".

The third solution isn't good for us. 10D1 are literature-history group, 10D2 are math-physics and 10D3 are math-informatic. So we can't swap these subgroups.

Our school will not grow because of our building and our town We are about at maximum...