/****************************************************************************** * Top contributors (to current version): * Mudathir Mohamed, Aina Niemetz * * This file is part of the cvc5 project. * * Copyright (c) 2009-2025 by the authors listed in the file AUTHORS * in the top-level source directory and their institutional affiliations. * All rights reserved. See the file COPYING in the top-level source * directory for licensing information. * **************************************************************************** * * A simple demonstration of reasoning about bags. */ #include #include using namespace std; using namespace cvc5; int main() { TermManager tm; Solver slv(tm); slv.setLogic("ALL"); // Produce models slv.setOption("produce-models", "true"); slv.setOption("incremental", "true"); Sort bag = tm.mkBagSort(tm.getStringSort()); Term A = tm.mkConst(bag, "A"); Term B = tm.mkConst(bag, "B"); Term C = tm.mkConst(bag, "C"); Term x = tm.mkConst(tm.getStringSort(), "x"); Term intersectionAC = tm.mkTerm(Kind::BAG_INTER_MIN, {A, C}); Term intersectionBC = tm.mkTerm(Kind::BAG_INTER_MIN, {B, C}); // union disjoint does not distribute over intersection { Term unionDisjointAB = tm.mkTerm(Kind::BAG_UNION_DISJOINT, {A, B}); Term lhs = tm.mkTerm(Kind::BAG_INTER_MIN, {unionDisjointAB, C}); Term rhs = tm.mkTerm(Kind::BAG_UNION_DISJOINT, {intersectionAC, intersectionBC}); Term guess = tm.mkTerm(Kind::EQUAL, {lhs, rhs}); cout << "cvc5 reports: " << guess.notTerm() << " is " << slv.checkSatAssuming(guess.notTerm()) << "." << endl; cout << A << ": " << slv.getValue(A) << endl; cout << B << ": " << slv.getValue(B) << endl; cout << C << ": " << slv.getValue(C) << endl; cout << lhs << ": " << slv.getValue(lhs) << endl; cout << rhs << ": " << slv.getValue(rhs) << endl; } // union max distributes over intersection { Term unionMaxAB = tm.mkTerm(Kind::BAG_UNION_MAX, {A, B}); Term lhs = tm.mkTerm(Kind::BAG_INTER_MIN, {unionMaxAB, C}); Term rhs = tm.mkTerm(Kind::BAG_UNION_MAX, {intersectionAC, intersectionBC}); Term theorem = tm.mkTerm(Kind::EQUAL, {lhs, rhs}); cout << "cvc5 reports: " << theorem.notTerm() << " is " << slv.checkSatAssuming(theorem.notTerm()) << "." << endl; } // Verify emptbag is a subbag of any bag { Term emptybag = tm.mkEmptyBag(bag); Term theorem = tm.mkTerm(Kind::BAG_SUBBAG, {emptybag, A}); cout << "cvc5 reports: " << theorem.notTerm() << " is " << slv.checkSatAssuming(theorem.notTerm()) << "." << endl; } // find an element with multiplicity 4 in the disjoint union of // ; {|"a", "a", "b", "b", "b"|} and {|"b", "c", "c"|} { Term one = tm.mkInteger(1); Term two = tm.mkInteger(2); Term three = tm.mkInteger(3); Term four = tm.mkInteger(4); Term a = tm.mkString("a"); Term b = tm.mkString("b"); Term c = tm.mkString("c"); Term bag_a_2 = tm.mkTerm(Kind::BAG_MAKE, {a, two}); Term bag_b_3 = tm.mkTerm(Kind::BAG_MAKE, {b, three}); Term bag_b_1 = tm.mkTerm(Kind::BAG_MAKE, {b, one}); Term bag_c_2 = tm.mkTerm(Kind::BAG_MAKE, {c, two}); Term bag_a_2_b_3 = tm.mkTerm(Kind::BAG_UNION_DISJOINT, {bag_a_2, bag_b_3}); Term bag_b_1_c_2 = tm.mkTerm(Kind::BAG_UNION_DISJOINT, {bag_b_1, bag_c_2}); Term union_disjoint = tm.mkTerm(Kind::BAG_UNION_DISJOINT, {bag_a_2_b_3, bag_b_1_c_2}); Term count_x = tm.mkTerm(Kind::BAG_COUNT, {x, union_disjoint}); Term e = tm.mkTerm(Kind::EQUAL, {four, count_x}); Result result = slv.checkSatAssuming(e); cout << "cvc5 reports: " << e << " is " << result << "." << endl; if (result.isSat()) { cout << x << ": " << slv.getValue(x) << endl; } } }