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/********************* */
/*! \file simple_vc_compat_cxx.cpp
** \verbatim
** Original author: Morgan Deters
** Major contributors: none
** Minor contributors (to current version): none
** This file is part of the CVC4 project.
** Copyright (c) 2009-2013 New York University and The University of Iowa
** See the file COPYING in the top-level source directory for licensing
** information.\endverbatim
**
** \brief A simple demonstration of the C++ compatibility interface
** (quite similar to the old CVC3 C++ interface)
**
** A simple demonstration of the C++ compatibility interface (quite
** similar to the old CVC3 C++ interface). Note that the library is
** named "libcvc4compat," to mark it as being part of CVC4, but the
** header file is "cvc3_compat.h" to indicate the similarity to the
** CVC3 interface, and the namespace is "CVC3". CVC3::Expr and
** CVC4::Expr are incompatible; to avoid confusion, it is best to not
** include both the CVC3 and CVC4 interface headers.
**/
#include <iostream>
// #include <cvc4/compat/cvc3_compat.h> // use this after CVC4 is properly installed
#include "compat/cvc3_compat.h"
using namespace std;
using namespace CVC3;
int main() {
ValidityChecker* vc = ValidityChecker::create();
// Prove that for integers x and y:
// x > 0 AND y > 0 => 2x + y >= 3
Type integer = vc->intType();
Expr x = vc->varExpr("x", integer);
Expr y = vc->varExpr("y", integer);
Expr zero = vc->ratExpr(0);
Expr x_positive = vc->gtExpr(x, zero);
Expr y_positive = vc->gtExpr(y, zero);
Expr two = vc->ratExpr(2);
Expr twox = vc->multExpr(two, x);
Expr twox_plus_y = vc->plusExpr(twox, y);
Expr three = vc->ratExpr(3);
Expr twox_plus_y_geq_3 = vc->geExpr(twox_plus_y, three);
Expr formula = vc->impliesExpr(vc->andExpr(x_positive, y_positive),
twox_plus_y_geq_3);
cout << "Checking validity of formula " << formula << " with CVC4." << endl;
cout << "CVC4 should report VALID." << endl;
cout << "Result from CVC4 is: " << vc->query(formula) << endl;
return 0;
}
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