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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 <iostream>
#include <cvc4/cvc4.h>
using namespace std;
using namespace CVC4;
int main() {
ExprManager em;
SmtEngine smt(&em);
// Prove that the following is unsatisfiable:
// forall x. P( x ) ^ ~P( 5 )
Type integer = em.integerType();
Type boolean = em.booleanType();
Type integerPredicate = em.mkFunctionType(integer, boolean);
Expr p = em.mkVar("P", integerPredicate);
Expr x = em.mkBoundVar("x", integer);
// make forall x. P( x )
Expr var_list = em.mkExpr(kind::BOUND_VAR_LIST, x);
Expr px = em.mkExpr(kind::APPLY_UF, p, x);
Expr quantpospx = em.mkExpr(kind::FORALL, var_list, px);
cout << "Made expression : " << quantpospx << endl;
//make ~P( 5 )
Expr five = em.mkConst(Rational(5));
Expr pfive = em.mkExpr(kind::APPLY_UF, p, five);
Expr negpfive = em.mkExpr(kind::NOT, pfive);
cout << "Made expression : " << negpfive << endl;
Expr formula = em.mkExpr(kind::AND, quantpospx, negpfive);
smt.assertFormula(formula);
cout << "Checking SAT after asserting " << formula << " to CVC4." << endl;
cout << "CVC4 should report unsat." << endl;
cout << "Result from CVC4 is: " << smt.checkSat() << endl;
SmtEngine smtp(&em);
// this version has a pattern e.g. in smt2 syntax (forall ((x Int)) (! (P x ) :pattern ((P x))))
Expr pattern = em.mkExpr(kind::INST_PATTERN, px);
Expr pattern_list = em.mkExpr(kind::INST_PATTERN_LIST, pattern);
Expr quantpospx_pattern = em.mkExpr(kind::FORALL, var_list, px, pattern_list);
cout << "Made expression : " << quantpospx_pattern << endl;
Expr formula_pattern = em.mkExpr(kind::AND, quantpospx_pattern, negpfive);
smtp.assertFormula(formula_pattern);
cout << "Checking SAT after asserting " << formula_pattern << " to CVC4." << endl;
cout << "CVC4 should report unsat." << endl;
cout << "Result from CVC4 is: " << smtp.checkSat() << endl;
return 0;
}
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