Files
cvc5/examples/api/cpp/sygus-fun.cpp
2022-04-05 20:38:57 +00:00

113 lines
3.4 KiB
C++

/******************************************************************************
* Top contributors (to current version):
* Abdalrhman Mohamed, Mathias Preiner, Andrew Reynolds
*
* This file is part of the cvc5 project.
*
* Copyright (c) 2009-2022 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 the Sygus API.
*
* A simple demonstration of how to use the Sygus API to synthesize max and min
* functions.
*/
#include <cvc5/cvc5.h>
#include <iostream>
#include "utils.h"
using namespace cvc5;
int main()
{
Solver slv;
// required options
slv.setOption("sygus", "true");
slv.setOption("incremental", "false");
// set the logic
slv.setLogic("LIA");
Sort integer = slv.getIntegerSort();
Sort boolean = slv.getBooleanSort();
// declare input variables for the functions-to-synthesize
Term x = slv.mkVar(integer, "x");
Term y = slv.mkVar(integer, "y");
// declare the grammar non-terminals
Term start = slv.mkVar(integer, "Start");
Term start_bool = slv.mkVar(boolean, "StartBool");
// define the rules
Term zero = slv.mkInteger(0);
Term one = slv.mkInteger(1);
Term plus = slv.mkTerm(ADD, {start, start});
Term minus = slv.mkTerm(SUB, {start, start});
Term ite = slv.mkTerm(ITE, {start_bool, start, start});
Term And = slv.mkTerm(AND, {start_bool, start_bool});
Term Not = slv.mkTerm(NOT, {start_bool});
Term leq = slv.mkTerm(LEQ, {start, start});
// create the grammar object
Grammar g = slv.mkGrammar({x, y}, {start, start_bool});
// bind each non-terminal to its rules
g.addRules(start, {zero, one, x, y, plus, minus, ite});
g.addRules(start_bool, {And, Not, leq});
// declare the functions-to-synthesize. Optionally, provide the grammar
// constraints
Term max = slv.synthFun("max", {x, y}, integer, g);
Term min = slv.synthFun("min", {x, y}, integer);
// declare universal variables.
Term varX = slv.declareSygusVar("x", integer);
Term varY = slv.declareSygusVar("y", integer);
Term max_x_y = slv.mkTerm(APPLY_UF, {max, varX, varY});
Term min_x_y = slv.mkTerm(APPLY_UF, {min, varX, varY});
// add semantic constraints
// (constraint (>= (max x y) x))
slv.addSygusConstraint(slv.mkTerm(GEQ, {max_x_y, varX}));
// (constraint (>= (max x y) y))
slv.addSygusConstraint(slv.mkTerm(GEQ, {max_x_y, varY}));
// (constraint (or (= x (max x y))
// (= y (max x y))))
slv.addSygusConstraint(slv.mkTerm(OR,
{slv.mkTerm(EQUAL, {max_x_y, varX}),
slv.mkTerm(EQUAL, {max_x_y, varY})}));
// (constraint (= (+ (max x y) (min x y))
// (+ x y)))
slv.addSygusConstraint(slv.mkTerm(
EQUAL,
{slv.mkTerm(ADD, {max_x_y, min_x_y}), slv.mkTerm(ADD, {varX, varY})}));
// print solutions if available
if (slv.checkSynth().hasSolution())
{
// Output should be equivalent to:
// (
// (define-fun max ((x Int) (y Int)) Int (ite (<= x y) y x))
// (define-fun min ((x Int) (y Int)) Int (ite (<= x y) x y))
// )
std::vector<Term> terms = {max, min};
utils::printSynthSolutions(terms, slv.getSynthSolutions(terms));
}
return 0;
}