Example #1
0
        public void GcdRootTest()
        {
            //(x-5)(x-7)(x-23)(x-1)(x-55)(x-17)(x-22)(x-2)(x-99)(x-100)(x-31)(x-50)x

            var arr        = new BigInteger[] { 0, 101, 17, 17, 91, 38, 15, 28, 98, 49, 74, 97, 16, 1 };
            var mod        = 107;
            var poly       = new Polynomial(arr, mod);
            var rootFinder = new GcdRootFinder();
            var actual     = rootFinder.FindRoots(poly, mod).Select(x => (x + mod) % mod).OrderBy(x => x).ToList();
            var expected   = new List <long>()
            {
                0, 5, 7, 23, 1, 55, 17, 22, 2, 99, 100, 31, 50
            }.OrderBy(x => x).ToList();

            Assert.AreEqual(actual.Count(), expected.Count());
            for (int i = 0; i < expected.Count(); i++)
            {
                if ((actual[i] + mod) % mod != (expected[i] + mod) % mod)
                {
                    throw new Exception();
                }
            }
        }
Example #2
0
File: SNFS.cs Project: zzfeed/GNFS
        public BigInteger FindFactor()
        {
            var timer = new Stopwatch();

            timer.Start();
            _polyInfo = _generator.GeneratePolynomial();
            Console.WriteLine(_number.Value());
            Console.WriteLine("f(x)=" + _polyInfo.Polynomial);
            Console.WriteLine("Root=" + _polyInfo.Root);

            var rootFinder             = new GcdRootFinder();
            var algFbBuilder           = new AlgebraicFactorbaseBuilder(_polyInfo.Polynomial, rootFinder, _algebraicPrimeBound);
            var rationalFbBuilder      = new RationalFactorbaseBuilder(_polyInfo.Root, _rationalPrimeBound);
            var quadraticCharFbBuilder = new QuadraticCharactersBuilder(_polyInfo.Polynomial, rootFinder, _algebraicPrimeBound, _quadraticCharFbSize);

            var rationalFb = rationalFbBuilder.Build();

            var quadraticCharFb = quadraticCharFbBuilder.Build();
            var algFb           = algFbBuilder.Build();
            var sieve           = new LogSieve();

            Console.WriteLine("\nRational factorbase size: " + rationalFb.Elements.Count);
            Console.WriteLine("Algebraic factorbase size: " + algFb.Elements.Count);
            Console.WriteLine("Quadratic characters factorbase size: " + quadraticCharFb.Elements.Count);
            Console.WriteLine("Init time: " + timer.Elapsed);
            timer.Reset();
            timer.Start();
            var pairs =
                sieve.Sieve(
                    (algFb.Elements.Count + rationalFb.Elements.Count + quadraticCharFb.Elements.Count + _kerDim + 1),
                    new SieveOptions(_sieveSize, -_sieveSize, algFb, rationalFb, _polyInfo.Polynomial, _polyInfo.Root));

            Console.WriteLine();
            Console.WriteLine(pairs.Count + " relations collected.");
            Console.WriteLine("Sieve time: " + timer.Elapsed);
            timer.Reset();
            timer.Start();
            var matrixBuilder = new MatrixBuilder();
            var matrix        = matrixBuilder.Build(pairs, rationalFb, algFb, quadraticCharFb, _polyInfo.Root, _polyInfo.Polynomial);
            var matrixSolver  = new GaussianEliminationOverGf2();


            //Console.WriteLine("{0}x{1} matrix builded. ",matrix.ColumnsCount,matrix.RowsCount);
            var solutions = matrixSolver.Solve(matrix);

            //  var solutions =matrix.Solve();
            Console.WriteLine();
            Console.WriteLine("Linear algebra time: " + timer.Elapsed);
            Console.WriteLine("{0} solution computed. ", solutions.Count);
            timer.Reset();
            timer.Start();


            var polyMath = new PolynomialMath(-1);
            var df       = new PolynomialDerivative().Derivative(_polyInfo.Polynomial);
            var sqrDf    = polyMath.Mul(df, df);

            var solutionsCheked = -1;

            foreach (var solution in solutions)
            {
                timer.Reset();
                timer.Start();
                var        sqr      = new Polynomial(new BigInteger[] { 1 });
                BigInteger sqrtNorm = 1;
                BigInteger x        = 1;

                for (int i = 0; i < solution.Length; i++)
                {
                    if (solution[i] == 1)
                    {
                        var tmp = new Polynomial(new BigInteger[] { pairs[i].Item1, pairs[i].Item2 });
                        x  *= pairs[i].Item1 + _polyInfo.Root * pairs[i].Item2;
                        sqr = polyMath.Rem(polyMath.Mul(tmp, sqr), _polyInfo.Polynomial);
                        var normCalculator = new FirstDegreeElementsNormCalculator(_polyInfo.Polynomial, pairs[i].Item2);
                        sqrtNorm *= normCalculator.CalculateNorm(pairs[i].Item1);
                    }
                }
                x *= sqrDf.Value(_polyInfo.Root);
                if (x < 0)
                {
                    throw new Exception();
                }
                sqr = polyMath.Rem(polyMath.Mul(sqrDf, sqr), _polyInfo.Polynomial);
                var integerSqrt = new IntegerSquareRoot();
                var sqrtX       = integerSqrt.Sqrt(x);
                if (sqrtX * sqrtX != x)
                {
                    if (sqrtX * sqrtX != x)
                    {
                        if (sqrtX * sqrtX != x)
                        {
                            throw new Exception();
                        }
                    }
                }


                var algSqrt = new AlgebraicSqrt();


                sqrtNorm = BigInteger.Abs(sqrtNorm);
                var tmpNorm = sqrtNorm;
                sqrtNorm = integerSqrt.Sqrt(BigInteger.Abs(sqrtNorm));
                timer.Stop();
                Console.WriteLine(timer.Elapsed + " Умножение");



                if (sqrtNorm * sqrtNorm != tmpNorm)
                {
                    if (sqrtNorm * sqrtNorm != tmpNorm)
                    {
                        if (sqrtNorm * sqrtNorm != tmpNorm)
                        {
                            throw new Exception();
                        }
                    }
                }
                timer.Reset();
                timer.Start();
                var sqrt = algSqrt.Sqrt(sqr, _polyInfo.Polynomial, df, sqrtNorm);
                timer.Stop();
                Console.WriteLine(timer.Elapsed + " Квадратный корень");
                if (algSqrt.DontExist)
                {
                    Console.Write("\r{0}/{1} solutions cheked. (BAD SQRT)    ", ++solutionsCheked, solutions.Count);
                    continue;
                }
                var sqrtY = sqrt.Value(_polyInfo.Root);

                var check = polyMath.Rem(polyMath.Mul(sqrt, sqrt), _polyInfo.Polynomial);
                if (check != sqr)
                {
                    var primes = new EratosthenesSieve().GetPrimes(5, 10000);
                    int i;
                    for (i = 0; i < primes.Length; i++)
                    {
                        if (!algSqrt.IsSqr(sqr, _polyInfo.Polynomial, primes[i]))
                        {
                            break;
                        }
                    }
                    if (i == primes.Length)
                    {
                        throw new Exception();
                    }
                    Console.Write("\r{0}/{1} solutions cheked. (BAD SQRT)    ", ++solutionsCheked, solutions.Count);
                    continue;
                }
                if ((sqrtY * sqrtY - sqrtX * sqrtX) % _number.Value() != 0)
                {
                    throw new Exception();
                }
                var factor = BigInteger.GreatestCommonDivisor(sqrtX - sqrtY, _number.Value());
                if (factor > 1 && factor < _number.Value())
                {
                    Console.Write("\r{0}/{1} solutions cheked                ", ++solutionsCheked, solutions.Count);
                    return(factor);
                }
                Console.Write("\r{0}/{1} solutions cheked. (BAD SOLUTION)", ++solutionsCheked, solutions.Count);
            }
            Console.Write("\r{0}/{1} solutions cheked.                ", solutionsCheked, solutions.Count);
            return(1);
        }