4.2.2.1. All-Different and related constraints

In this section: all_different, all_different_except, all_different_except_0, all_disjoint, all_equal, nvalue, symmetric_all_different.

all_different

 predicate all_different(array [$X] of var int: x)

 predicate all_different(array [$X] of var set of int: x)

 predicate all_different(array [$X] of var opt int: x)

1, 2.: Constrain the elements in the array x to be pairwise different.

Constrain the non-absent elements in the array x to be pairwise different. The absent value <> is allowed to occur multiple times.

all_different_except

predicate all_different_except(array [$X] of var int: vs,
                               set of int: S)

Constrain the elements of the array of integers vs to be pairwise different except for those values that appear in the set S.

all_different_except_0

predicate all_different_except_0(array [$X] of var int: vs)

Constrain the elements of the array of integers vs to be pairwise different except for those elements that are assigned the value 0.

all_disjoint

predicate all_disjoint(array [$X] of var set of int: S)

Constrain the array of sets of integers S to be pairwise disjoint.

all_equal

predicate all_equal(array [$X] of var int: x)
predicate all_equal(array [$X] of var set of int: x)

Constrain the elements of the array x to be all equal.

nvalue

 predicate nvalue(var int: n, array [$X] of var int: x)

 predicate nvalue(var int: n, array [$X] of var opt int: x)

 function var int: nvalue(array [$X] of var int: x)

 function var int: nvalue(array [$X] of var opt int: x)

1, 2.: Requires that the number of distinct values in x is n.
3, 4.: Returns the number of distinct values in x.

symmetric_all_different

predicate symmetric_all_different(array [int] of var int: x)

Requires the array of integers x to be all different, and for all i, x[i]=j \(\rightarrow\) x[j]=i.