/// <summary> /// Generates a slightly randomized expression. /// </summary> static BoolExpr MkRandomExpr(Context ctx, System.Random rng) { int limit = 1073741823; Sort i = ctx.IntSort; Sort b = ctx.BoolSort; Symbol sr1 = ctx.MkSymbol(rng.Next(0, limit)); Symbol sr2 = ctx.MkSymbol(rng.Next(0, limit)); Symbol sr3 = ctx.MkSymbol(rng.Next(0, limit)); FuncDecl r1 = ctx.MkFuncDecl(sr1, i, b); FuncDecl r2 = ctx.MkFuncDecl(sr2, i, b); FuncDecl r3 = ctx.MkFuncDecl(sr3, i, b); Symbol s = ctx.MkSymbol(rng.Next(0, limit)); Expr x = ctx.MkConst(s, i); BoolExpr r1x = (BoolExpr)ctx.MkApp(r1, x); BoolExpr r2x = (BoolExpr)ctx.MkApp(r2, x); BoolExpr r3x = (BoolExpr)ctx.MkApp(r3, x); Expr[] vars = { x }; BoolExpr rl1 = ctx.MkForall(vars, ctx.MkImplies(r1x, r2x)); BoolExpr rl2 = ctx.MkForall(vars, ctx.MkImplies(r2x, r1x)); BoolExpr rl3 = (BoolExpr)ctx.MkApp(r1, ctx.MkInt(3)); BoolExpr q = (BoolExpr)ctx.MkApp(r3, ctx.MkInt(2)); BoolExpr a1 = ctx.MkNot(q); BoolExpr q1 = ctx.MkExists(vars, ctx.MkAnd(r3x, r2x)); BoolExpr q2 = ctx.MkExists(vars, ctx.MkAnd(r3x, r1x)); BoolExpr[] all = { a1, q1, q2 }; return ctx.MkAnd(all); }
/// <summary> /// Create axiom: function f is injective in the i-th argument. /// </summary> /// <remarks> /// The following axiom is produced: /// <c> /// forall (x_0, ..., x_n) finv(f(x_0, ..., x_i, ..., x_{n-1})) = x_i /// </c> /// Where, <code>finv</code>is a fresh function declaration. /// </summary> public static BoolExpr InjAxiom(Context ctx, FuncDecl f, int i) { Sort[] domain = f.Domain; uint sz = f.DomainSize; if (i >= sz) { Console.WriteLine("failed to create inj axiom"); return null; } /* declare the i-th inverse of f: finv */ Sort finv_domain = f.Range; Sort finv_range = domain[i]; FuncDecl finv = ctx.MkFuncDecl("f_fresh", finv_domain, finv_range); /* allocate temporary arrays */ Expr[] xs = new Expr[sz]; Symbol[] names = new Symbol[sz]; Sort[] types = new Sort[sz]; /* fill types, names and xs */ for (uint j = 0; j < sz; j++) { types[j] = domain[j]; names[j] = ctx.MkSymbol(String.Format("x_{0}", j)); xs[j] = ctx.MkBound(j, types[j]); } Expr x_i = xs[i]; /* create f(x_0, ..., x_i, ..., x_{n-1}) */ Expr fxs = f[xs]; /* create f_inv(f(x_0, ..., x_i, ..., x_{n-1})) */ Expr finv_fxs = finv[fxs]; /* create finv(f(x_0, ..., x_i, ..., x_{n-1})) = x_i */ Expr eq = ctx.MkEq(finv_fxs, x_i); /* use f(x_0, ..., x_i, ..., x_{n-1}) as the pattern for the quantifier */ Pattern p = ctx.MkPattern(new Expr[] { fxs }); /* create & assert quantifier */ BoolExpr q = ctx.MkForall( types, /* types of quantified variables */ names, /* names of quantified variables */ eq, 1, new Pattern[] { p } /* patterns */); return q; }
public void Run() { using (Context ctx = new Context()) { Symbol s1 = ctx.MkSymbol(1); Symbol s2 = ctx.MkSymbol(1); Symbol s3 = ctx.MkSymbol(2); Sort[] domain = new Sort[0]; Sort range = ctx.IntSort; TestDriver.CheckAssertion("a1", s1 == s2); TestDriver.CheckAssertion("a2", s1 != s3); TestDriver.CheckAssertion("a3", ctx.MkSymbol("x") != s1); TestDriver.CheckAssertion("a4", ctx.MkSymbol("x") == ctx.MkSymbol("x")); TestDriver.CheckAssertion("a5", ctx.MkFuncDecl("f", domain, range) == ctx.MkFuncDecl("f", domain, range)); TestDriver.CheckAssertion("a6", ctx.MkFuncDecl("f", domain, range) != ctx.MkFuncDecl("g", domain, range)); TestDriver.CheckAssertion("a7", ctx.MkUninterpretedSort("s") == ctx.MkUninterpretedSort("s")); TestDriver.CheckAssertion("a8", ctx.MkUninterpretedSort("s") != ctx.MkUninterpretedSort("t")); TestDriver.CheckAssertion("a9", ctx.MkUninterpretedSort("s") != ctx.IntSort); TestDriver.CheckAssertion("a10", ctx.MkConst("x", range) == ctx.MkConst("x", range)); TestDriver.CheckAssertion("a11", ctx.MkConst("x", range) == ctx.MkConst(ctx.MkSymbol("x"), range)); TestDriver.CheckAssertion("a12", ctx.MkConst("x", range) != ctx.MkConst("y", range)); } }
/// <summary> /// A simple array example. /// </summary> /// <param name="ctx"></param> static void ArrayExample1(Context ctx) { Console.WriteLine("ArrayExample1"); Goal g = ctx.MkGoal(true); ArraySort asort = ctx.MkArraySort(ctx.IntSort, ctx.MkBitVecSort(32)); ArrayExpr aex = (ArrayExpr)ctx.MkConst(ctx.MkSymbol("MyArray"), asort); Expr sel = ctx.MkSelect(aex, ctx.MkInt(0)); g.Assert(ctx.MkEq(sel, ctx.MkBV(42, 32))); Symbol xs = ctx.MkSymbol("x"); IntExpr xc = (IntExpr)ctx.MkConst(xs, ctx.IntSort); Symbol fname = ctx.MkSymbol("f"); Sort[] domain = { ctx.IntSort }; FuncDecl fd = ctx.MkFuncDecl(fname, domain, ctx.IntSort); Expr[] fargs = { ctx.MkConst(xs, ctx.IntSort) }; IntExpr fapp = (IntExpr)ctx.MkApp(fd, fargs); g.Assert(ctx.MkEq(ctx.MkAdd(xc, fapp), ctx.MkInt(123))); Solver s = ctx.MkSolver(); foreach (BoolExpr a in g.Formulas) s.Assert(a); Console.WriteLine("Solver: " + s); Status q = s.Check(); Console.WriteLine("Status: " + q); if (q != Status.SATISFIABLE) throw new TestFailedException(); Console.WriteLine("Model = " + s.Model); Console.WriteLine("Interpretation of MyArray:\n" + s.Model.FuncInterp(aex.FuncDecl)); Console.WriteLine("Interpretation of x:\n" + s.Model.ConstInterp(xc)); Console.WriteLine("Interpretation of f:\n" + s.Model.FuncInterp(fd)); Console.WriteLine("Interpretation of MyArray as Term:\n" + s.Model.FuncInterp(aex.FuncDecl)); }
static void ModelConverterTest(Context ctx) { Console.WriteLine("ModelConverterTest"); ArithExpr xr = (ArithExpr)ctx.MkConst(ctx.MkSymbol("x"), ctx.MkRealSort()); ArithExpr yr = (ArithExpr)ctx.MkConst(ctx.MkSymbol("y"), ctx.MkRealSort()); Goal g4 = ctx.MkGoal(true); g4.Assert(ctx.MkGt(xr, ctx.MkReal(10, 1))); g4.Assert(ctx.MkEq(yr, ctx.MkAdd(xr, ctx.MkReal(1, 1)))); g4.Assert(ctx.MkGt(yr, ctx.MkReal(1, 1))); ApplyResult ar = ApplyTactic(ctx, ctx.MkTactic("simplify"), g4); if (ar.NumSubgoals == 1 && (ar.Subgoals[0].IsDecidedSat || ar.Subgoals[0].IsDecidedUnsat)) throw new TestFailedException(); ar = ApplyTactic(ctx, ctx.AndThen(ctx.MkTactic("simplify"), ctx.MkTactic("solve-eqs")), g4); if (ar.NumSubgoals == 1 && (ar.Subgoals[0].IsDecidedSat || ar.Subgoals[0].IsDecidedUnsat)) throw new TestFailedException(); Solver s = ctx.MkSolver(); foreach (BoolExpr e in ar.Subgoals[0].Formulas) s.Assert(e); Status q = s.Check(); Console.WriteLine("Solver says: " + q); Console.WriteLine("Model: \n" + s.Model); Console.WriteLine("Converted Model: \n" + ar.ConvertModel(0, s.Model)); if (q != Status.SATISFIABLE) throw new TestFailedException(); }
public static void FloatingPointExample2(Context ctx) { Console.WriteLine("FloatingPointExample2"); FPSort double_sort = ctx.MkFPSort(11, 53); FPRMSort rm_sort = ctx.MkFPRoundingModeSort(); FPRMExpr rm = (FPRMExpr)ctx.MkConst(ctx.MkSymbol("rm"), rm_sort); BitVecExpr x = (BitVecExpr)ctx.MkConst(ctx.MkSymbol("x"), ctx.MkBitVecSort(64)); FPExpr y = (FPExpr)ctx.MkConst(ctx.MkSymbol("y"), double_sort); FPExpr fp_val = ctx.MkFP(42, double_sort); BoolExpr c1 = ctx.MkEq(y, fp_val); BoolExpr c2 = ctx.MkEq(x, ctx.MkFPToBV(rm, y, 64, false)); BoolExpr c3 = ctx.MkEq(x, ctx.MkBV(42, 64)); BoolExpr c4 = ctx.MkEq(ctx.MkNumeral(42, ctx.RealSort), ctx.MkFPToReal(fp_val)); BoolExpr c5 = ctx.MkAnd(c1, c2, c3, c4); Console.WriteLine("c5 = " + c5); /* Generic solver */ Solver s = ctx.MkSolver(); s.Assert(c5); Console.WriteLine(s); if (s.Check() != Status.SATISFIABLE) throw new TestFailedException(); Console.WriteLine("OK, model: {0}", s.Model.ToString()); }
/// <summary> /// Some basic expression casting tests. /// </summary> static void CastingTest(Context ctx) { Console.WriteLine("CastingTest"); Sort[] domain = { ctx.BoolSort, ctx.BoolSort }; FuncDecl f = ctx.MkFuncDecl("f", domain, ctx.BoolSort); AST upcast = ctx.MkFuncDecl(ctx.MkSymbol("q"), domain, ctx.BoolSort); try { FuncDecl downcast = (FuncDecl)f; // OK } catch (InvalidCastException) { throw new TestFailedException(); } try { Expr uc = (Expr)upcast; throw new TestFailedException(); // should not be reachable! } catch (InvalidCastException) { } Symbol s = ctx.MkSymbol(42); IntSymbol si = s as IntSymbol; if (si == null) throw new TestFailedException(); try { IntSymbol si2 = (IntSymbol)s; } catch (InvalidCastException) { throw new TestFailedException(); } s = ctx.MkSymbol("abc"); StringSymbol ss = s as StringSymbol; if (ss == null) throw new TestFailedException(); try { StringSymbol ss2 = (StringSymbol)s; } catch (InvalidCastException) { throw new TestFailedException(); } try { IntSymbol si2 = (IntSymbol)s; throw new TestFailedException(); // unreachable } catch { } Sort srt = ctx.MkBitVecSort(32); BitVecSort bvs = null; try { bvs = (BitVecSort)srt; } catch (InvalidCastException) { throw new TestFailedException(); } if (bvs.Size != 32) throw new TestFailedException(); Expr q = ctx.MkAdd(ctx.MkInt(1), ctx.MkInt(2)); Expr q2 = q.Args[1]; Sort qs = q2.Sort; if (qs as IntSort == null) throw new TestFailedException(); try { IntSort isrt = (IntSort)qs; } catch (InvalidCastException) { throw new TestFailedException(); } AST a = ctx.MkInt(42); Expr ae = a as Expr; if (ae == null) throw new TestFailedException(); ArithExpr aae = a as ArithExpr; if (aae == null) throw new TestFailedException(); IntExpr aie = a as IntExpr; if (aie == null) throw new TestFailedException(); IntNum ain = a as IntNum; if (ain == null) throw new TestFailedException(); Expr[][] earr = new Expr[2][]; earr[0] = new Expr[2]; earr[1] = new Expr[2]; earr[0][0] = ctx.MkTrue(); earr[0][1] = ctx.MkTrue(); earr[1][0] = ctx.MkFalse(); earr[1][1] = ctx.MkFalse(); foreach (Expr[] ea in earr) foreach (Expr e in ea) { try { Expr ns = ctx.MkNot((BoolExpr)e); BoolExpr ens = (BoolExpr)ns; } catch (InvalidCastException) { throw new TestFailedException(); } } }
static void QuantifierExample2(Context ctx) { Console.WriteLine("QuantifierExample2"); Expr q1, q2; FuncDecl f = ctx.MkFuncDecl("f", ctx.IntSort, ctx.IntSort); FuncDecl g = ctx.MkFuncDecl("g", ctx.IntSort, ctx.IntSort); // Quantifier with Exprs as the bound variables. { Expr x = ctx.MkConst("x", ctx.IntSort); Expr y = ctx.MkConst("y", ctx.IntSort); Expr f_x = ctx.MkApp(f, x); Expr f_y = ctx.MkApp(f, y); Expr g_y = ctx.MkApp(g, y); Pattern[] pats = new Pattern[] { ctx.MkPattern(new Expr[] { f_x, g_y }) }; Expr[] no_pats = new Expr[] { f_y }; Expr[] bound = new Expr[2] { x, y }; Expr body = ctx.MkAnd(ctx.MkEq(f_x, f_y), ctx.MkEq(f_y, g_y)); q1 = ctx.MkForall(bound, body, 1, null, no_pats, ctx.MkSymbol("q"), ctx.MkSymbol("sk")); Console.WriteLine("{0}", q1); } // Quantifier with de-Brujin indices. { Expr x = ctx.MkBound(1, ctx.IntSort); Expr y = ctx.MkBound(0, ctx.IntSort); Expr f_x = ctx.MkApp(f, x); Expr f_y = ctx.MkApp(f, y); Expr g_y = ctx.MkApp(g, y); Pattern[] pats = new Pattern[] { ctx.MkPattern(new Expr[] { f_x, g_y }) }; Expr[] no_pats = new Expr[] { f_y }; Symbol[] names = new Symbol[] { ctx.MkSymbol("x"), ctx.MkSymbol("y") }; Sort[] sorts = new Sort[] { ctx.IntSort, ctx.IntSort }; Expr body = ctx.MkAnd(ctx.MkEq(f_x, f_y), ctx.MkEq(f_y, g_y)); q2 = ctx.MkForall(sorts, names, body, 1, null, // pats, no_pats, ctx.MkSymbol("q"), ctx.MkSymbol("sk") ); Console.WriteLine("{0}", q2); } Console.WriteLine("{0}", (q1.Equals(q2))); }
/// <summary> /// Create an enumeration data type. /// </summary> public static void EnumExample(Context ctx) { Console.WriteLine("EnumExample"); Symbol name = ctx.MkSymbol("fruit"); EnumSort fruit = ctx.MkEnumSort(ctx.MkSymbol("fruit"), new Symbol[] { ctx.MkSymbol("apple"), ctx.MkSymbol("banana"), ctx.MkSymbol("orange") }); Console.WriteLine("{0}", (fruit.Consts[0])); Console.WriteLine("{0}", (fruit.Consts[1])); Console.WriteLine("{0}", (fruit.Consts[2])); Console.WriteLine("{0}", (fruit.TesterDecls[0])); Console.WriteLine("{0}", (fruit.TesterDecls[1])); Console.WriteLine("{0}", (fruit.TesterDecls[2])); Expr apple = fruit.Consts[0]; Expr banana = fruit.Consts[1]; Expr orange = fruit.Consts[2]; /* Apples are different from oranges */ Prove(ctx, ctx.MkNot(ctx.MkEq(apple, orange))); /* Apples pass the apple test */ Prove(ctx, (BoolExpr)ctx.MkApp(fruit.TesterDecls[0], apple)); /* Oranges fail the apple test */ Disprove(ctx, (BoolExpr)ctx.MkApp(fruit.TesterDecls[0], orange)); Prove(ctx, (BoolExpr)ctx.MkNot((BoolExpr)ctx.MkApp(fruit.TesterDecls[0], orange))); Expr fruity = ctx.MkConst("fruity", fruit); /* If something is fruity, then it is an apple, banana, or orange */ Prove(ctx, ctx.MkOr(new BoolExpr[] { ctx.MkEq(fruity, apple), ctx.MkEq(fruity, banana), ctx.MkEq(fruity, orange) })); }
/// <summary> /// Demonstrates how to initialize the parser symbol table. /// </summary> public static void ParserExample3(Context ctx) { Console.WriteLine("ParserExample3"); /* declare function g */ Sort I = ctx.MkIntSort(); FuncDecl g = ctx.MkFuncDecl("g", new Sort[] { I, I }, I); BoolExpr ca = CommAxiom(ctx, g); ctx.ParseSMTLIBString("(benchmark tst :formula (forall (x Int) (y Int) (implies (= x y) (= (gg x 0) (gg 0 y)))))", null, null, new Symbol[] { ctx.MkSymbol("gg") }, new FuncDecl[] { g }); BoolExpr thm = ctx.SMTLIBFormulas[0]; Console.WriteLine("formula: {0}", thm); Prove(ctx, thm, false, ca); }
/// <summary> /// Demonstrates how to initialize the parser symbol table. /// </summary> public static void ParserExample2(Context ctx) { Console.WriteLine("ParserExample2"); Symbol[] declNames = { ctx.MkSymbol("a"), ctx.MkSymbol("b") }; FuncDecl a = ctx.MkConstDecl(declNames[0], ctx.MkIntSort()); FuncDecl b = ctx.MkConstDecl(declNames[1], ctx.MkIntSort()); FuncDecl[] decls = new FuncDecl[] { a, b }; ctx.ParseSMTLIBString("(benchmark tst :formula (> a b))", null, null, declNames, decls); BoolExpr f = ctx.SMTLIBFormulas[0]; Console.WriteLine("formula: {0}", f); Check(ctx, f, Status.SATISFIABLE); }
/// <summary> /// Tuples. /// </summary> /// <remarks>Check that the projection of a tuple /// returns the corresponding element.</remarks> public static void TupleExample(Context ctx) { Console.WriteLine("TupleExample"); Sort int_type = ctx.IntSort; TupleSort tuple = ctx.MkTupleSort( ctx.MkSymbol("mk_tuple"), // name of tuple constructor new Symbol[] { ctx.MkSymbol("first"), ctx.MkSymbol("second") }, // names of projection operators new Sort[] { int_type, int_type } // types of projection operators ); FuncDecl first = tuple.FieldDecls[0]; // declarations are for projections FuncDecl second = tuple.FieldDecls[1]; Expr x = ctx.MkConst("x", int_type); Expr y = ctx.MkConst("y", int_type); Expr n1 = tuple.MkDecl[x, y]; Expr n2 = first[n1]; BoolExpr n3 = ctx.MkEq(x, n2); Console.WriteLine("Tuple example: {0}", n3); Prove(ctx, n3); }
/// <summary> /// Prove <tt>x = y implies g(x) = g(y)</tt>, and /// disprove <tt>x = y implies g(g(x)) = g(y)</tt>. /// </summary> /// <remarks>This function demonstrates how to create uninterpreted /// types and functions.</remarks> public static void ProveExample1(Context ctx) { Console.WriteLine("ProveExample1"); /* create uninterpreted type. */ Sort U = ctx.MkUninterpretedSort(ctx.MkSymbol("U")); /* declare function g */ FuncDecl g = ctx.MkFuncDecl("g", U, U); /* create x and y */ Expr x = ctx.MkConst("x", U); Expr y = ctx.MkConst("y", U); /* create g(x), g(y) */ Expr gx = g[x]; Expr gy = g[y]; /* assert x = y */ BoolExpr eq = ctx.MkEq(x, y); /* prove g(x) = g(y) */ BoolExpr f = ctx.MkEq(gx, gy); Console.WriteLine("prove: x = y implies g(x) = g(y)"); Prove(ctx, ctx.MkImplies(eq, f)); /* create g(g(x)) */ Expr ggx = g[gx]; /* disprove g(g(x)) = g(y) */ f = ctx.MkEq(ggx, gy); Console.WriteLine("disprove: x = y implies g(g(x)) = g(y)"); Disprove(ctx, ctx.MkImplies(eq, f)); /* Print the model using the custom model printer */ Model m = Check(ctx, ctx.MkNot(f), Status.SATISFIABLE); Console.WriteLine(m); }
public static Z3.Symbol Symbol(this Z3C ctx, int index) => ctx.MkSymbol(index);
public static Z3.Symbol Symbol(this Z3C ctx, string name) => ctx.MkSymbol(name);
/// <summary> /// Sudoku solving example. /// </summary> static void SudokuExample(Context ctx) { Console.WriteLine("SudokuExample"); // 9x9 matrix of integer variables IntExpr[][] X = new IntExpr[9][]; for (uint i = 0; i < 9; i++) { X[i] = new IntExpr[9]; for (uint j = 0; j < 9; j++) X[i][j] = (IntExpr)ctx.MkConst(ctx.MkSymbol("x_" + (i + 1) + "_" + (j + 1)), ctx.IntSort); } // each cell contains a value in {1, ..., 9} Expr[][] cells_c = new Expr[9][]; for (uint i = 0; i < 9; i++) { cells_c[i] = new BoolExpr[9]; for (uint j = 0; j < 9; j++) cells_c[i][j] = ctx.MkAnd(ctx.MkLe(ctx.MkInt(1), X[i][j]), ctx.MkLe(X[i][j], ctx.MkInt(9))); } // each row contains a digit at most once BoolExpr[] rows_c = new BoolExpr[9]; for (uint i = 0; i < 9; i++) rows_c[i] = ctx.MkDistinct(X[i]); // each column contains a digit at most once BoolExpr[] cols_c = new BoolExpr[9]; for (uint j = 0; j < 9; j++) { IntExpr[] column = new IntExpr[9]; for (uint i = 0; i < 9; i++) column[i] = X[i][j]; cols_c[j] = ctx.MkDistinct(column); } // each 3x3 square contains a digit at most once BoolExpr[][] sq_c = new BoolExpr[3][]; for (uint i0 = 0; i0 < 3; i0++) { sq_c[i0] = new BoolExpr[3]; for (uint j0 = 0; j0 < 3; j0++) { IntExpr[] square = new IntExpr[9]; for (uint i = 0; i < 3; i++) for (uint j = 0; j < 3; j++) square[3 * i + j] = X[3 * i0 + i][3 * j0 + j]; sq_c[i0][j0] = ctx.MkDistinct(square); } } BoolExpr sudoku_c = ctx.MkTrue(); foreach (BoolExpr[] t in cells_c) sudoku_c = ctx.MkAnd(ctx.MkAnd(t), sudoku_c); sudoku_c = ctx.MkAnd(ctx.MkAnd(rows_c), sudoku_c); sudoku_c = ctx.MkAnd(ctx.MkAnd(cols_c), sudoku_c); foreach (BoolExpr[] t in sq_c) sudoku_c = ctx.MkAnd(ctx.MkAnd(t), sudoku_c); // sudoku instance, we use '0' for empty cells int[,] instance = {{0,0,0,0,9,4,0,3,0}, {0,0,0,5,1,0,0,0,7}, {0,8,9,0,0,0,0,4,0}, {0,0,0,0,0,0,2,0,8}, {0,6,0,2,0,1,0,5,0}, {1,0,2,0,0,0,0,0,0}, {0,7,0,0,0,0,5,2,0}, {9,0,0,0,6,5,0,0,0}, {0,4,0,9,7,0,0,0,0}}; BoolExpr instance_c = ctx.MkTrue(); for (uint i = 0; i < 9; i++) for (uint j = 0; j < 9; j++) instance_c = ctx.MkAnd(instance_c, (BoolExpr) ctx.MkITE(ctx.MkEq(ctx.MkInt(instance[i, j]), ctx.MkInt(0)), ctx.MkTrue(), ctx.MkEq(X[i][j], ctx.MkInt(instance[i, j])))); Solver s = ctx.MkSolver(); s.Assert(sudoku_c); s.Assert(instance_c); if (s.Check() == Status.SATISFIABLE) { Model m = s.Model; Expr[,] R = new Expr[9, 9]; for (uint i = 0; i < 9; i++) for (uint j = 0; j < 9; j++) R[i, j] = m.Evaluate(X[i][j]); Console.WriteLine("Sudoku solution:"); for (uint i = 0; i < 9; i++) { for (uint j = 0; j < 9; j++) Console.Write(" " + R[i, j]); Console.WriteLine(); } } else { Console.WriteLine("Failed to solve sudoku"); throw new TestFailedException(); } }
/// <summary> /// A basic example of how to use quantifiers. /// </summary> static void QuantifierExample1(Context ctx) { Console.WriteLine("QuantifierExample"); Sort[] types = new Sort[3]; IntExpr[] xs = new IntExpr[3]; Symbol[] names = new Symbol[3]; IntExpr[] vars = new IntExpr[3]; for (uint j = 0; j < 3; j++) { types[j] = ctx.IntSort; names[j] = ctx.MkSymbol(String.Format("x_{0}", j)); xs[j] = (IntExpr)ctx.MkConst(names[j], types[j]); vars[j] = (IntExpr)ctx.MkBound(2 - j, types[j]); // <-- vars reversed! } Expr body_vars = ctx.MkAnd(ctx.MkEq(ctx.MkAdd(vars[0], ctx.MkInt(1)), ctx.MkInt(2)), ctx.MkEq(ctx.MkAdd(vars[1], ctx.MkInt(2)), ctx.MkAdd(vars[2], ctx.MkInt(3)))); Expr body_const = ctx.MkAnd(ctx.MkEq(ctx.MkAdd(xs[0], ctx.MkInt(1)), ctx.MkInt(2)), ctx.MkEq(ctx.MkAdd(xs[1], ctx.MkInt(2)), ctx.MkAdd(xs[2], ctx.MkInt(3)))); Expr x = ctx.MkForall(types, names, body_vars, 1, null, null, ctx.MkSymbol("Q1"), ctx.MkSymbol("skid1")); Console.WriteLine("Quantifier X: " + x.ToString()); Expr y = ctx.MkForall(xs, body_const, 1, null, null, ctx.MkSymbol("Q2"), ctx.MkSymbol("skid2")); Console.WriteLine("Quantifier Y: " + y.ToString()); }
/// <summary> /// Create a list datatype. /// </summary> public static void ListExample(Context ctx) { Console.WriteLine("ListExample"); Sort int_ty; ListSort int_list; Expr nil, l1, l2, x, y, u, v; BoolExpr fml, fml1; int_ty = ctx.MkIntSort(); int_list = ctx.MkListSort(ctx.MkSymbol("int_list"), int_ty); nil = ctx.MkConst(int_list.NilDecl); l1 = ctx.MkApp(int_list.ConsDecl, ctx.MkInt(1), nil); l2 = ctx.MkApp(int_list.ConsDecl, ctx.MkInt(2), nil); /* nil != cons(1, nil) */ Prove(ctx, ctx.MkNot(ctx.MkEq(nil, l1))); /* cons(2,nil) != cons(1, nil) */ Prove(ctx, ctx.MkNot(ctx.MkEq(l1, l2))); /* cons(x,nil) = cons(y, nil) => x = y */ x = ctx.MkConst("x", int_ty); y = ctx.MkConst("y", int_ty); l1 = ctx.MkApp(int_list.ConsDecl, x, nil); l2 = ctx.MkApp(int_list.ConsDecl, y, nil); Prove(ctx, ctx.MkImplies(ctx.MkEq(l1, l2), ctx.MkEq(x, y))); /* cons(x,u) = cons(x, v) => u = v */ u = ctx.MkConst("u", int_list); v = ctx.MkConst("v", int_list); l1 = ctx.MkApp(int_list.ConsDecl, x, u); l2 = ctx.MkApp(int_list.ConsDecl, y, v); Prove(ctx, ctx.MkImplies(ctx.MkEq(l1, l2), ctx.MkEq(u, v))); Prove(ctx, ctx.MkImplies(ctx.MkEq(l1, l2), ctx.MkEq(x, y))); /* is_nil(u) or is_cons(u) */ Prove(ctx, ctx.MkOr((BoolExpr)ctx.MkApp(int_list.IsNilDecl, u), (BoolExpr)ctx.MkApp(int_list.IsConsDecl, u))); /* occurs check u != cons(x,u) */ Prove(ctx, ctx.MkNot(ctx.MkEq(u, l1))); /* destructors: is_cons(u) => u = cons(head(u),tail(u)) */ fml1 = ctx.MkEq(u, ctx.MkApp(int_list.ConsDecl, ctx.MkApp(int_list.HeadDecl, u), ctx.MkApp(int_list.TailDecl, u))); fml = ctx.MkImplies((BoolExpr)ctx.MkApp(int_list.IsConsDecl, u), fml1); Console.WriteLine("Formula {0}", fml); Prove(ctx, fml); Disprove(ctx, fml1); }
/// <summary> /// Some basic tests. /// </summary> static void BasicTests(Context ctx) { Console.WriteLine("BasicTests"); Symbol qi = ctx.MkSymbol(1); Symbol fname = ctx.MkSymbol("f"); Symbol x = ctx.MkSymbol("x"); Symbol y = ctx.MkSymbol("y"); Sort bs = ctx.MkBoolSort(); Sort[] domain = { bs, bs }; FuncDecl f = ctx.MkFuncDecl(fname, domain, bs); Expr fapp = ctx.MkApp(f, ctx.MkConst(x, bs), ctx.MkConst(y, bs)); Expr[] fargs2 = { ctx.MkFreshConst("cp", bs) }; Sort[] domain2 = { bs }; Expr fapp2 = ctx.MkApp(ctx.MkFreshFuncDecl("fp", domain2, bs), fargs2); BoolExpr trivial_eq = ctx.MkEq(fapp, fapp); BoolExpr nontrivial_eq = ctx.MkEq(fapp, fapp2); Goal g = ctx.MkGoal(true); g.Assert(trivial_eq); g.Assert(nontrivial_eq); Console.WriteLine("Goal: " + g); Solver solver = ctx.MkSolver(); foreach (BoolExpr a in g.Formulas) solver.Assert(a); if (solver.Check() != Status.SATISFIABLE) throw new TestFailedException(); ApplyResult ar = ApplyTactic(ctx, ctx.MkTactic("simplify"), g); if (ar.NumSubgoals == 1 && (ar.Subgoals[0].IsDecidedSat || ar.Subgoals[0].IsDecidedUnsat)) throw new TestFailedException(); ar = ApplyTactic(ctx, ctx.MkTactic("smt"), g); if (ar.NumSubgoals != 1 || !ar.Subgoals[0].IsDecidedSat) throw new TestFailedException(); g.Assert(ctx.MkEq(ctx.MkNumeral(1, ctx.MkBitVecSort(32)), ctx.MkNumeral(2, ctx.MkBitVecSort(32)))); ar = ApplyTactic(ctx, ctx.MkTactic("smt"), g); if (ar.NumSubgoals != 1 || !ar.Subgoals[0].IsDecidedUnsat) throw new TestFailedException(); Goal g2 = ctx.MkGoal(true, true); ar = ApplyTactic(ctx, ctx.MkTactic("smt"), g2); if (ar.NumSubgoals != 1 || !ar.Subgoals[0].IsDecidedSat) throw new TestFailedException(); g2 = ctx.MkGoal(true, true); g2.Assert(ctx.MkFalse()); ar = ApplyTactic(ctx, ctx.MkTactic("smt"), g2); if (ar.NumSubgoals != 1 || !ar.Subgoals[0].IsDecidedUnsat) throw new TestFailedException(); Goal g3 = ctx.MkGoal(true, true); Expr xc = ctx.MkConst(ctx.MkSymbol("x"), ctx.IntSort); Expr yc = ctx.MkConst(ctx.MkSymbol("y"), ctx.IntSort); g3.Assert(ctx.MkEq(xc, ctx.MkNumeral(1, ctx.IntSort))); g3.Assert(ctx.MkEq(yc, ctx.MkNumeral(2, ctx.IntSort))); BoolExpr constr = ctx.MkEq(xc, yc); g3.Assert(constr); ar = ApplyTactic(ctx, ctx.MkTactic("smt"), g3); if (ar.NumSubgoals != 1 || !ar.Subgoals[0].IsDecidedUnsat) throw new TestFailedException(); ModelConverterTest(ctx); // Real num/den test. RatNum rn = ctx.MkReal(42, 43); Expr inum = rn.Numerator; Expr iden = rn.Denominator; Console.WriteLine("Numerator: " + inum + " Denominator: " + iden); if (inum.ToString() != "42" || iden.ToString() != "43") throw new TestFailedException(); if (rn.ToDecimalString(3) != "0.976?") throw new TestFailedException(); BigIntCheck(ctx, ctx.MkReal("-1231231232/234234333")); BigIntCheck(ctx, ctx.MkReal("-123123234234234234231232/234234333")); BigIntCheck(ctx, ctx.MkReal("-234234333")); BigIntCheck(ctx, ctx.MkReal("234234333/2")); string bn = "1234567890987654321"; if (ctx.MkInt(bn).BigInteger.ToString() != bn) throw new TestFailedException(); if (ctx.MkBV(bn, 128).BigInteger.ToString() != bn) throw new TestFailedException(); if (ctx.MkBV(bn, 32).BigInteger.ToString() == bn) throw new TestFailedException(); // Error handling test. try { IntExpr i = ctx.MkInt("1/2"); throw new TestFailedException(); // unreachable } catch (Z3Exception) { } }
/// <summary> /// Create a forest of trees. /// </summary> /// <remarks> /// forest ::= nil | cons(tree, forest) /// tree ::= nil | cons(forest, forest) /// </remarks> public static void ForestExample(Context ctx) { Console.WriteLine("ForestExample"); Sort tree, forest; FuncDecl nil1_decl, is_nil1_decl, cons1_decl, is_cons1_decl, car1_decl, cdr1_decl; FuncDecl nil2_decl, is_nil2_decl, cons2_decl, is_cons2_decl, car2_decl, cdr2_decl; Expr nil1, nil2, t1, t2, t3, t4, f1, f2, f3, l1, l2, x, y, u, v; // // Declare the names of the accessors for cons. // Then declare the sorts of the accessors. // For this example, all sorts refer to the new types 'forest' and 'tree' // being declared, so we pass in null for both sorts1 and sorts2. // On the other hand, the sort_refs arrays contain the indices of the // two new sorts being declared. The first element in sort1_refs // points to 'tree', which has index 1, the second element in sort1_refs array // points to 'forest', which has index 0. // Symbol[] head_tail1 = new Symbol[] { ctx.MkSymbol("head"), ctx.MkSymbol("tail") }; Sort[] sorts1 = new Sort[] { null, null }; uint[] sort1_refs = new uint[] { 1, 0 }; // the first item points to a tree, the second to a forest Symbol[] head_tail2 = new Symbol[] { ctx.MkSymbol("car"), ctx.MkSymbol("cdr") }; Sort[] sorts2 = new Sort[] { null, null }; uint[] sort2_refs = new uint[] { 0, 0 }; // both items point to the forest datatype. Constructor nil1_con, cons1_con, nil2_con, cons2_con; Constructor[] constructors1 = new Constructor[2], constructors2 = new Constructor[2]; Symbol[] sort_names = { ctx.MkSymbol("forest"), ctx.MkSymbol("tree") }; /* build a forest */ nil1_con = ctx.MkConstructor(ctx.MkSymbol("nil"), ctx.MkSymbol("is_nil"), null, null, null); cons1_con = ctx.MkConstructor(ctx.MkSymbol("cons1"), ctx.MkSymbol("is_cons1"), head_tail1, sorts1, sort1_refs); constructors1[0] = nil1_con; constructors1[1] = cons1_con; /* build a tree */ nil2_con = ctx.MkConstructor(ctx.MkSymbol("nil2"), ctx.MkSymbol("is_nil2"), null, null, null); cons2_con = ctx.MkConstructor(ctx.MkSymbol("cons2"), ctx.MkSymbol("is_cons2"), head_tail2, sorts2, sort2_refs); constructors2[0] = nil2_con; constructors2[1] = cons2_con; Constructor[][] clists = new Constructor[][] { constructors1, constructors2 }; Sort[] sorts = ctx.MkDatatypeSorts(sort_names, clists); forest = sorts[0]; tree = sorts[1]; // // Now that the datatype has been created. // Query the constructors for the constructor // functions, testers, and field accessors. // nil1_decl = nil1_con.ConstructorDecl; is_nil1_decl = nil1_con.TesterDecl; cons1_decl = cons1_con.ConstructorDecl; is_cons1_decl = cons1_con.TesterDecl; FuncDecl[] cons1_accessors = cons1_con.AccessorDecls; car1_decl = cons1_accessors[0]; cdr1_decl = cons1_accessors[1]; nil2_decl = nil2_con.ConstructorDecl; is_nil2_decl = nil2_con.TesterDecl; cons2_decl = cons2_con.ConstructorDecl; is_cons2_decl = cons2_con.TesterDecl; FuncDecl[] cons2_accessors = cons2_con.AccessorDecls; car2_decl = cons2_accessors[0]; cdr2_decl = cons2_accessors[1]; nil1 = ctx.MkConst(nil1_decl); nil2 = ctx.MkConst(nil2_decl); f1 = ctx.MkApp(cons1_decl, nil2, nil1); t1 = ctx.MkApp(cons2_decl, nil1, nil1); t2 = ctx.MkApp(cons2_decl, f1, nil1); t3 = ctx.MkApp(cons2_decl, f1, f1); t4 = ctx.MkApp(cons2_decl, nil1, f1); f2 = ctx.MkApp(cons1_decl, t1, nil1); f3 = ctx.MkApp(cons1_decl, t1, f1); /* nil != cons(nil,nil) */ Prove(ctx, ctx.MkNot(ctx.MkEq(nil1, f1))); Prove(ctx, ctx.MkNot(ctx.MkEq(nil2, t1))); /* cons(x,u) = cons(x, v) => u = v */ u = ctx.MkConst("u", forest); v = ctx.MkConst("v", forest); x = ctx.MkConst("x", tree); y = ctx.MkConst("y", tree); l1 = ctx.MkApp(cons1_decl, x, u); l2 = ctx.MkApp(cons1_decl, y, v); Prove(ctx, ctx.MkImplies(ctx.MkEq(l1, l2), ctx.MkEq(u, v))); Prove(ctx, ctx.MkImplies(ctx.MkEq(l1, l2), ctx.MkEq(x, y))); /* is_nil(u) or is_cons(u) */ Prove(ctx, ctx.MkOr((BoolExpr)ctx.MkApp(is_nil1_decl, u), (BoolExpr)ctx.MkApp(is_cons1_decl, u))); /* occurs check u != cons(x,u) */ Prove(ctx, ctx.MkNot(ctx.MkEq(u, l1))); }
/// <summary> /// Constructs a Z3 solver to be used. /// </summary> internal void ConstructSolver(Z3BaseParams parameters) { // If Z3 is there already, kill it if (_context != null) { DestructSolver(false); } _context = new Context(); _optSolver = _context.MkOptimize(); var p = _context.MkParams(); switch (parameters.OptKind) { case OptimizationKind.BoundingBox: p.Add("priority", _context.MkSymbol("box")); break; case OptimizationKind.Lexicographic: p.Add("priority", _context.MkSymbol("lex")); break; case OptimizationKind.ParetoOptimal: p.Add("priority", _context.MkSymbol("pareto")); break; default: Debug.Assert(false, String.Format("Unknown optimization option {0}", parameters.OptKind)); break; } switch (parameters.CardinalityAlgorithm) { case CardinalityAlgorithm.FuMalik: p.Add("maxsat_engine", _context.MkSymbol("fu_malik")); break; case CardinalityAlgorithm.CoreMaxSAT: p.Add("maxsat_engine", _context.MkSymbol("core_maxsat")); break; default: Debug.Assert(false, String.Format("Unknown cardinality algorithm option {0}", parameters.CardinalityAlgorithm)); break; } switch (parameters.PseudoBooleanAlgorithm) { case PseudoBooleanAlgorithm.WeightedMaxSAT: p.Add("wmaxsat_engine", _context.MkSymbol("wmax")); break; case PseudoBooleanAlgorithm.IterativeWeightedMaxSAT: p.Add("wmaxsat_engine", _context.MkSymbol("iwmax")); break; case PseudoBooleanAlgorithm.BisectionWeightedMaxSAT: p.Add("wmaxsat_engine", _context.MkSymbol("bwmax")); break; case PseudoBooleanAlgorithm.WeightedPartialMaxSAT2: p.Add("wmaxsat_engine", _context.MkSymbol("wpm2")); break; default: Debug.Assert(false, String.Format("Unknown pseudo-boolean algorithm option {0}", parameters.PseudoBooleanAlgorithm)); break; } switch (parameters.ArithmeticStrategy) { case ArithmeticStrategy.Basic: p.Add("engine", _context.MkSymbol("basic")); break; case ArithmeticStrategy.Farkas: p.Add("engine", _context.MkSymbol("farkas")); break; default: Debug.Assert(false, String.Format("Unknown arithmetic strategy option {0}", parameters.ArithmeticStrategy)); break; } _optSolver.Parameters = p; }
/// <summary> /// Demonstrate how to use #Eval on tuples. /// </summary> public static void EvalExample2(Context ctx) { Console.WriteLine("EvalExample2"); Sort int_type = ctx.IntSort; TupleSort tuple = ctx.MkTupleSort( ctx.MkSymbol("mk_tuple"), // name of tuple constructor new Symbol[] { ctx.MkSymbol("first"), ctx.MkSymbol("second") }, // names of projection operators new Sort[] { int_type, int_type } // types of projection operators ); FuncDecl first = tuple.FieldDecls[0]; // declarations are for projections FuncDecl second = tuple.FieldDecls[1]; Expr tup1 = ctx.MkConst("t1", tuple); Expr tup2 = ctx.MkConst("t2", tuple); Solver solver = ctx.MkSolver(); /* assert tup1 != tup2 */ solver.Assert(ctx.MkNot(ctx.MkEq(tup1, tup2))); /* assert first tup1 = first tup2 */ solver.Assert(ctx.MkEq(ctx.MkApp(first, tup1), ctx.MkApp(first, tup2))); /* find model for the constraints above */ Model model = null; if (Status.SATISFIABLE == solver.Check()) { model = solver.Model; Console.WriteLine("{0}", model); Console.WriteLine("evaluating tup1 {0}", (model.Evaluate(tup1))); Console.WriteLine("evaluating tup2 {0}", (model.Evaluate(tup2))); Console.WriteLine("evaluating second(tup2) {0}", (model.Evaluate(ctx.MkApp(second, tup2)))); } else { Console.WriteLine("BUG, the constraints are satisfiable."); } }