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deletemin(?Var, +List, -Rest)
Select from List the variable Var which has the smallest lower domain bound,
and return the rest of the list.
- A variable.
- A term unifying with a list of domain variables or integers.
- A list of domain variables or integers.
This predicate is used in labeling procedures. Especially when labeling
start times in scheduling problems, it is often a good strategy to start
with the earliest possible tasks, because fixing those will cause useful
bounds propagation on the start times of the other tasks. This predicate
selects from a list the variable with the smallest lower bound. Numbers
are treated as if they were variables with singleton domains.
Fails if List is empty.
start_time_labeling() :- !.
deletemin(X, Vars, Rest),
deleteff / 3, deleteffc / 3, indomain / 1, labeling / 1