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

104 lines
3.0 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 Grammar to add syntax constraints to
* the Sygus solution for the identity function.
*/
#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();
// declare input variable for the function-to-synthesize
Term x = slv.mkVar(integer, "x");
// declare the grammar non-terminal
Term start = slv.mkVar(integer, "Start");
// define the rules
Term zero = slv.mkInteger(0);
Term neg_x = slv.mkTerm(NEG, {x});
Term plus = slv.mkTerm(ADD, {x, start});
// create the grammar object
Grammar g1 = slv.mkGrammar({x}, {start});
// bind each non-terminal to its rules
g1.addRules(start, {neg_x, plus});
// copy the first grammar with all of its non-termainals and their rules
Grammar g2 = g1;
Grammar g3 = g1;
// add parameters as rules for the start symbol. Similar to "(Variable Int)"
g2.addAnyVariable(start);
// declare the functions-to-synthesize
Term id1 = slv.synthFun("id1", {x}, integer, g1);
Term id2 = slv.synthFun("id2", {x}, integer, g2);
g3.addRule(start, zero);
Term id3 = slv.synthFun("id3", {x}, integer, g3);
// g1 is reusable as long as it remains unmodified after first use
Term id4 = slv.synthFun("id4", {x}, integer, g1);
// declare universal variables.
Term varX = slv.declareSygusVar("x", integer);
Term id1_x = slv.mkTerm(APPLY_UF, {id1, varX});
Term id2_x = slv.mkTerm(APPLY_UF, {id2, varX});
Term id3_x = slv.mkTerm(APPLY_UF, {id3, varX});
Term id4_x = slv.mkTerm(APPLY_UF, {id4, varX});
// add semantic constraints
// (constraint (= (id1 x) (id2 x) (id3 x) (id4 x) x))
slv.addSygusConstraint(
slv.mkTerm(EQUAL, {{id1_x, id2_x, id3_x, id4_x, varX}}));
// print solutions if available
if (slv.checkSynth().hasSolution())
{
// Output should be equivalent to:
// (
// (define-fun id1 ((x Int)) Int (+ x (+ x (- x))))
// (define-fun id2 ((x Int)) Int x)
// (define-fun id3 ((x Int)) Int (+ x 0))
// (define-fun id4 ((x Int)) Int (+ x (+ x (- x))))
// )
std::vector<Term> terms = {id1, id2, id3, id4};
utils::printSynthSolutions(terms, slv.getSynthSolutions(terms));
}
return 0;
}