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cvc5/examples/api/cpp/sygus-fun.cpp
2025-01-23 17:54:20 +00:00

114 lines
3.5 KiB
C++

/******************************************************************************
* Top contributors (to current version):
* Abdalrhman Mohamed, Aina Niemetz, Mathias Preiner
*
* This file is part of the cvc5 project.
*
* Copyright (c) 2009-2025 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()
{
TermManager tm;
Solver slv(tm);
// required options
slv.setOption("sygus", "true");
slv.setOption("incremental", "false");
// set the logic
slv.setLogic("LIA");
Sort integer = tm.getIntegerSort();
Sort boolean = tm.getBooleanSort();
// declare input variables for the functions-to-synthesize
Term x = tm.mkVar(integer, "x");
Term y = tm.mkVar(integer, "y");
// declare the grammar non-terminals
Term start = tm.mkVar(integer, "Start");
Term start_bool = tm.mkVar(boolean, "StartBool");
// define the rules
Term zero = tm.mkInteger(0);
Term one = tm.mkInteger(1);
Term plus = tm.mkTerm(Kind::ADD, {start, start});
Term minus = tm.mkTerm(Kind::SUB, {start, start});
Term ite = tm.mkTerm(Kind::ITE, {start_bool, start, start});
Term And = tm.mkTerm(Kind::AND, {start_bool, start_bool});
Term Not = tm.mkTerm(Kind::NOT, {start_bool});
Term leq = tm.mkTerm(Kind::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 = tm.mkTerm(Kind::APPLY_UF, {max, varX, varY});
Term min_x_y = tm.mkTerm(Kind::APPLY_UF, {min, varX, varY});
// add semantic constraints
// (constraint (>= (max x y) x))
slv.addSygusConstraint(tm.mkTerm(Kind::GEQ, {max_x_y, varX}));
// (constraint (>= (max x y) y))
slv.addSygusConstraint(tm.mkTerm(Kind::GEQ, {max_x_y, varY}));
// (constraint (or (= x (max x y))
// (= y (max x y))))
slv.addSygusConstraint(tm.mkTerm(Kind::OR,
{tm.mkTerm(Kind::EQUAL, {max_x_y, varX}),
tm.mkTerm(Kind::EQUAL, {max_x_y, varY})}));
// (constraint (= (+ (max x y) (min x y))
// (+ x y)))
slv.addSygusConstraint(tm.mkTerm(Kind::EQUAL,
{tm.mkTerm(Kind::ADD, {max_x_y, min_x_y}),
tm.mkTerm(Kind::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;
}