always-cautious/ortools-clone
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

speed up cut management; expand negated table constraints

Browse Source
This commit is contained in:
Laurent Perron
2020-03-11 17:53:22 +01:00
parent fc9553af86
commit 0ba997ada1
9 changed files with 160 additions and 93 deletions
Download Patch File Download Diff File Expand all files Collapse all files

39
ortools/sat/table.cc
View File

@@ -28,6 +28,7 @@
#include "ortools/base/stl_util.h"
#include "ortools/sat/sat_base.h"
#include "ortools/sat/sat_solver.h"
#include "ortools/sat/util.h"
#include "ortools/util/sorted_interval_list.h"
namespace operations_research {
@@ -239,44 +240,6 @@ void ExploreSubsetOfVariablesAndAddNegatedTables(
} // namespace
void CompressTuples(absl::Span<const int64> domain_sizes, int64 any_value,
std::vector<std::vector<int64>>* tuples) {
if (tuples->empty()) return;
// Remove duplicates if any.
gtl::STLSortAndRemoveDuplicates(tuples);
const int num_vars = (*tuples)[0].size();
std::vector<int> to_remove;
std::vector<int64> tuple_minus_var_i(num_vars - 1);
for (int i = 0; i < num_vars; ++i) {
const int domain_size = domain_sizes[i];
if (domain_size == 1) continue;
absl::flat_hash_map<const std::vector<int64>, std::vector<int>>
masked_tuples_to_indices;
for (int t = 0; t < tuples->size(); ++t) {
int out = 0;
for (int j = 0; j < num_vars; ++j) {
if (i == j) continue;
tuple_minus_var_i[out++] = (*tuples)[t][j];
}
masked_tuples_to_indices[tuple_minus_var_i].push_back(t);
}
to_remove.clear();
for (const auto& it : masked_tuples_to_indices) {
if (it.second.size() != domain_size) continue;
(*tuples)[it.second.front()][i] = any_value;
to_remove.insert(to_remove.end(), it.second.begin() + 1, it.second.end());
}
std::sort(to_remove.begin(), to_remove.end(), std::greater<int>());
for (const int t : to_remove) {
(*tuples)[t] = tuples->back();
tuples->pop_back();
}
}
}
// Makes a static decomposition of a table constraint into clauses.
// This uses an auxiliary vector of Literals tuple_literals.
// For every column col, and every value val of that column,