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/********************* */
/*! \file simple_vc_quant_cxx.cpp
** \verbatim
** Top contributors (to current version):
** Andrew Reynolds
** This file is part of the CVC4 project.
** Copyright (c) 2009-2020 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.\endverbatim
**
** \brief A simple demonstration of the C++ interface for quantifiers
**
** A simple demonstration of the C++ interface for quantifiers.
**/
#include <cvc4/api/cvc4cpp.h>
#include <iostream>
using namespace CVC4::api;
int main() {
Solver slv;
// Prove that the following is unsatisfiable:
// forall x. P( x ) ^ ~P( 5 )
Sort integer = slv.getIntegerSort();
Sort boolean = slv.getBooleanSort();
Sort integerPredicate = slv.mkFunctionSort(integer, boolean);
Term p = slv.mkConst(integerPredicate, "P");
Term x = slv.mkVar(integer, "x");
// make forall x. P( x )
Term var_list = slv.mkTerm(Kind::BOUND_VAR_LIST, x);
Term px = slv.mkTerm(Kind::APPLY_UF, p, x);
Term quantpospx = slv.mkTerm(Kind::FORALL, var_list, px);
std::cout << "Made expression : " << quantpospx << std::endl;
//make ~P( 5 )
Term five = slv.mkReal(5);
Term pfive = slv.mkTerm(Kind::APPLY_UF, p, five);
Term negpfive = slv.mkTerm(Kind::NOT, pfive);
std::cout << "Made expression : " << negpfive << std::endl;
Term formula = slv.mkTerm(Kind::AND, quantpospx, negpfive);
slv.assertFormula(formula);
std::cout << "Checking SAT after asserting " << formula << " to CVC4."
<< std::endl;
std::cout << "CVC4 should report unsat." << std::endl;
std::cout << "Result from CVC4 is: " << slv.checkSat() << std::endl;
slv.resetAssertions();
// this version has a pattern e.g. in smt2 syntax (forall ((x Int)) (! (P x ) :pattern ((P x))))
Term pattern = slv.mkTerm(Kind::INST_PATTERN, px);
Term pattern_list = slv.mkTerm(Kind::INST_PATTERN_LIST, pattern);
Term quantpospx_pattern =
slv.mkTerm(Kind::FORALL, var_list, px, pattern_list);
std::cout << "Made expression : " << quantpospx_pattern << std::endl;
Term formula_pattern = slv.mkTerm(Kind::AND, quantpospx_pattern, negpfive);
slv.assertFormula(formula_pattern);
std::cout << "Checking SAT after asserting " << formula_pattern << " to CVC4."
<< std::endl;
std::cout << "CVC4 should report unsat." << std::endl;
std::cout << "Result from CVC4 is: " << slv.checkSat() << std::endl;
return 0;
}
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