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Jip J. Dekker fad1b07018 Squashed 'software/minizinc/' content from commit 4f10c8205
git-subtree-dir: software/minizinc
git-subtree-split: 4f10c82056ffcb1041d7ffef29d77a7eef92cf76
2021-06-16 14:06:46 +10:00

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MiniZinc

include "fzn_steiner.mzn";
include "fzn_steiner_reif.mzn";
include "fzn_dsteiner.mzn";
include "fzn_dsteiner_reif.mzn";
include "weighted_spanning_tree.mzn";
/** @group globals.graph
Constrains the subgraph \a ns and \a es of a given directed graph to be a weighted spanning tree rooted at \a r of weight \a W.
@param N: the number of nodes in the given graph
@param E: the number of edges in the given graph
@param from: the leaving node 1..\a N for each edge
@param to: the entering node 1..\a N for each edge
@param w: the weight of each edge
@param r: the root node (which may be variable)
@param ns: a Boolean for each node whether it is in the subgraph
@param es: a Boolean for each edge whether it is in the subgraph
@param K: the weight of the tree
*/
predicate dsteiner(int: N, int: E, array[int] of int: from, array[int] of int: to, array[int] of int: w,
var int: r, array[int] of var bool: ns, array[int] of var bool: es, var int: K) =
assert(index_set(from) = 1..E,"dsteiner: index set of from must be 1..\(E)") /\
assert(index_set(to) = 1..E,"dsteiner: index set of to must be 1..\(E)") /\
assert(index_set(ns) = 1..N,"dsteiner: index set of ns must be 1..\(N)") /\
assert(index_set(es) = 1..E,"dsteiner: index set of es must be 1..\(E)") /\
assert(index_set(w) = 1..E,"dsteiner: index set of w must be 1..\(E)") /\
if forall(n in 1..N)(is_fixed(ns[n]) /\ fix(ns[n])) then
d_weighted_spanning_tree(N,E,from,to,w,r,es,K)
else
fzn_dsteiner(N,E,from,to,w,r,ns,es,K)
endif;
/** @group globals.graph
Constrains the set of edges \a es of a given undirected graph to be a weighted spanning tree of weight \a W.
@param N: the number of nodes in the given graph
@param E: the number of edges in the given graph
@param from: the leaving node 1..\a N for each edge
@param to: the entering node 1..\a N for each edge
@param w: the weight of each edge
@param ns: a Boolean for each node whether it is in the subgraph
@param es: a Boolean for each edge whether it is in the subgraph
@param K: the weight of the tree
**/
predicate steiner(int: N, int: E, array[int] of int: from, array[int] of int: to, array[int] of int: w,
array[int] of var bool: ns, array[int] of var bool: es, var int: K) =
assert(index_set(from) = 1..E,"steiner: index set of from must be 1..\(E)") /\
assert(index_set(to) = 1..E,"steiner: index set of to must be 1..\(E)") /\
assert(index_set(ns) = 1..N,"steiner: index set of ns must be 1..\(N)") /\
assert(index_set(es) = 1..E,"steiner: index set of es must be 1..\(E)") /\
assert(index_set(w) = 1..E,"steiner: index set of w must be 1..\(E)") /\
if forall(n in 1..N)(is_fixed(ns[n]) /\ fix(ns[n])) then
weighted_spanning_tree(N,E,from,to,w,es,K)
else
fzn_steiner(N,E,from,to,w,ns,es,K)
endif;
%-----------------------------------------------------------------------------%