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/******************************************************************************
* Top contributors (to current version):
* Mudathir Mohamed, Aina Niemetz, Daniel Larraz
*
* 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 api capabilities of cvc5.
*
*/
import io.github.cvc5.*;
import java.math.BigInteger;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
public class QuickStart
{
public static void main(String args[]) throws CVC5ApiException
{
// Create a term manager
//! [docs-java-quickstart-0 start]
TermManager tm = new TermManager();
//! [docs-java-quickstart-0 end]
// Create a solver
//! [docs-java-quickstart-1 start]
Solver solver = new Solver(tm);
//! [docs-java-quickstart-1 end]
{
// We will ask the solver to produce models and unsat cores,
// hence these options should be turned on.
//! [docs-java-quickstart-2 start]
solver.setOption("produce-models", "true");
solver.setOption("produce-unsat-cores", "true");
//! [docs-java-quickstart-2 end]
// The simplest way to set a logic for the solver is to choose "ALL".
// This enables all logics in the solver.
// Alternatively, "QF_ALL" enables all logics without quantifiers.
// To optimize the solver's behavior for a more specific logic,
// use the logic name, e.g. "QF_BV" or "QF_AUFBV".
// Set the logic
//! [docs-java-quickstart-3 start]
solver.setLogic("ALL");
//! [docs-java-quickstart-3 end]
// In this example, we will define constraints over reals and integers.
// Hence, we first obtain the corresponding sorts.
//! [docs-java-quickstart-4 start]
Sort realSort = tm.getRealSort();
Sort intSort = tm.getIntegerSort();
//! [docs-java-quickstart-4 end]
// x and y will be real variables, while a and b will be integer variables.
// Formally, their cpp type is Term,
// and they are called "constants" in SMT jargon:
//! [docs-java-quickstart-5 start]
Term x = tm.mkConst(realSort, "x");
Term y = tm.mkConst(realSort, "y");
Term a = tm.mkConst(intSort, "a");
Term b = tm.mkConst(intSort, "b");
//! [docs-java-quickstart-5 end]
// Our constraints regarding x and y will be:
//
// (1) 0 < x
// (2) 0 < y
// (3) x + y < 1
// (4) x <= y
//
//! [docs-java-quickstart-6 start]
// Formally, constraints are also terms. Their sort is Boolean.
// We will construct these constraints gradually,
// by defining each of their components.
// We start with the constant numerals 0 and 1:
Term zero = tm.mkReal(0);
Term one = tm.mkReal(1);
// Next, we construct the term x + y
Term xPlusY = tm.mkTerm(Kind.ADD, x, y);
// Now we can define the constraints.
// They use the operators +, <=, and <.
// In the API, these are denoted by ADD, LEQ, and LT.
// A list of available operators is available in:
// src/api/cpp/cvc5_kind.h
Term constraint1 = tm.mkTerm(Kind.LT, zero, x);
Term constraint2 = tm.mkTerm(Kind.LT, zero, y);
Term constraint3 = tm.mkTerm(Kind.LT, xPlusY, one);
Term constraint4 = tm.mkTerm(Kind.LEQ, x, y);
// Now we assert the constraints to the solver.
solver.assertFormula(constraint1);
solver.assertFormula(constraint2);
solver.assertFormula(constraint3);
solver.assertFormula(constraint4);
//! [docs-java-quickstart-6 end]
// Check if the formula is satisfiable, that is,
// are there real values for x and y that satisfy all the constraints?
//! [docs-java-quickstart-7 start]
Result r1 = solver.checkSat();
//! [docs-java-quickstart-7 end]
// The result is either SAT, UNSAT, or UNKNOWN.
// In this case, it is SAT.
//! [docs-java-quickstart-8 start]
System.out.println("expected: sat");
System.out.println("result: " + r1);
//! [docs-java-quickstart-8 end]
// We can get the values for x and y that satisfy the constraints.
//! [docs-java-quickstart-9 start]
Term xVal = solver.getValue(x);
Term yVal = solver.getValue(y);
//! [docs-java-quickstart-9 end]
// It is also possible to get values for compound terms,
// even if those did not appear in the original formula.
//! [docs-java-quickstart-10 start]
Term xMinusY = tm.mkTerm(Kind.SUB, x, y);
Term xMinusYVal = solver.getValue(xMinusY);
//! [docs-java-quickstart-10 end]
// Further, we can convert the values to java types
//! [docs-java-quickstart-11 start]
Pair<BigInteger, BigInteger> xPair = xVal.getRealValue();
Pair<BigInteger, BigInteger> yPair = yVal.getRealValue();
Pair<BigInteger, BigInteger> xMinusYPair = xMinusYVal.getRealValue();
System.out.println("value for x: " + xPair.first + "/" + xPair.second);
System.out.println("value for y: " + yPair.first + "/" + yPair.second);
System.out.println("value for x - y: " + xMinusYPair.first + "/" + xMinusYPair.second);
//! [docs-java-quickstart-11 end]
// Another way to independently compute the value of x - y would be
// to perform the (rational) arithmetic manually.
// However, for more complex terms,
// it is easier to let the solver do the evaluation.
//! [docs-java-quickstart-12 start]
Pair<BigInteger, BigInteger> xMinusYComputed =
new Pair<>(xPair.first.multiply(yPair.second).subtract(xPair.second.multiply(yPair.first)),
xPair.second.multiply(yPair.second));
BigInteger g = xMinusYComputed.first.gcd(xMinusYComputed.second);
xMinusYComputed = new Pair<>(xMinusYComputed.first.divide(g), xMinusYComputed.second.divide(g));
if (xMinusYComputed.equals(xMinusYPair))
{
System.out.println("computed correctly");
}
else
{
System.out.println("computed incorrectly");
}
//! [docs-java-quickstart-12 end]
// Next, we will check satisfiability of the same formula,
// only this time over integer variables a and b.
// We start by resetting assertions added to the solver.
//! [docs-java-quickstart-13 start]
solver.resetAssertions();
//! [docs-java-quickstart-13 end]
// Next, we assert the same assertions above with integers.
// This time, we inline the construction of terms
// to the assertion command.
//! [docs-java-quickstart-14 start]
solver.assertFormula(tm.mkTerm(Kind.LT, tm.mkInteger(0), a));
solver.assertFormula(tm.mkTerm(Kind.LT, tm.mkInteger(0), b));
solver.assertFormula(
tm.mkTerm(Kind.LT, tm.mkTerm(Kind.ADD, a, b), tm.mkInteger(1)));
solver.assertFormula(tm.mkTerm(Kind.LEQ, a, b));
//! [docs-java-quickstart-14 end]
// We check whether the revised assertion is satisfiable.
//! [docs-java-quickstart-15 start]
Result r2 = solver.checkSat();
// This time the formula is unsatisfiable
System.out.println("expected: unsat");
System.out.println("result: " + r2);
//! [docs-java-quickstart-15 end]
// We can query the solver for an unsatisfiable core, i.e., a subset
// of the assertions that is already unsatisfiable.
//! [docs-java-quickstart-16 start]
List<Term> unsatCore = Arrays.asList(solver.getUnsatCore());
System.out.println("unsat core size: " + unsatCore.size());
System.out.println("unsat core: ");
for (Term t : unsatCore)
{
System.out.println(t);
}
//! [docs-java-quickstart-16 end]
}
Context.deletePointers();
}
}
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