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<ConsistencyModule:> ham_path_offset(?Start,?End,+Succ,+Offset)

Constrains elements (offset by Offset) in Succ to form a Hamiltonian path from Start to End.
An integer or (domain) variable (array notation accepted)
An integer or (domain) variable (array notation accepted)
A collection of different (domain) variables or integers
Offset for Succ (An integer)


Succ is a collection of N elements presenting a digraph of N nodes, where the i'th element of Succ represents the successor to node i. The constraint enforces (Succ -Offset) to form a Hamiltonian path, a path through every node in the graph, visiting each node once, with Start giving the first node of the path, and End giving the last node of the path. Note that the Succ of the last node will be N+1, i.e. a dummy node not in the graph.

Note that the Gecode implementation of this constraint has index (node id) starting from 0, rather than 1. The value of Offset is incremented by 1 when the constraint is posted to Gecode. A version of this constraint with native Gecode indexing, i.e. without adjusting Offset, is available as ham_path_offset_g/4.

ConsistencyModule is the optional module specification to give the consistency level for the propagation for this constraint: gfd_gac for generalised arc consistency (domain consistency), and gfd_vc for value consistency.

This constraint is implemented by Gecode's path() constraint, with an actual offset of 1 + Offset.

See Also

ham_path_offset_g / 4