Activities time constraint confusing

[thanhnambkhn]

Dear Liviu Lalescu
I have some questions about Time constraints of FET, could you explain?
- What is the difference between 2 constraints: "2 activities are consecutive" and "2 activities are grouped"?
- I dont understand the constraint: "A students set works in an hourly interval max days per week", could you give an example? I have read the instruction but It is still not clear.

I am also not clear about "The description of FET's algorithm":
"- 1) Sort activities, most difficult first. Not critical step, but speeds up the algorithm maybe 10 times or more."
What does "most difficult" mean? How to know which activity is more difficult than other activies?
- How should I do if I want to understand the FET's algorithm in details (and to customize FET after that)?

Thank you so much.

[Volker Dirr]

groups vs consecutive:
grouped: the order doesn't matter. So activity 1 first then activity 2. Or activity 2 first then activity 1.
consecutive: fet care about the order. So always activity 1 first then activity 2.

[Volker Dirr]

for example you can choose the last hour of a day and say max 1. So students will have max one time the last hour.

[Volker Dirr]

difficult: an activity with a low number of allowed slots and a high number of conflicts to other activities.
easy: a high number of allowed slots and a low number of conflicts to other activities.

[Volker Dirr]

i don't understand your last question. you should start reading the AGPL. After that you should read the source code.

[thanhnambkhn]

Thank Volker Dirr.

The last question is ambiguous a little (and silly  maybe).
I mean that I am not understand clearly about FET algorithms currently. Reading source code is not useful now (maybe difficult and take a long time)

So could you give me a guide , to investigate and understand quickly about it? (I think after that, reading, customizing Source code is easier and more clearly)