% 10 operations replaces with UInt128/ulong.Mod10 methods
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@@ -20,10 +20,8 @@ public class MersenneNumberResidueCpuTester
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// Current residues
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q.Mod10_8_5_3(out ulong r10, out ulong r8, out ulong r5, out ulong r3);
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// Step residues for q += 2*p
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ulong step10 = (ulong)(twoP % 10UL) % 10UL;
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ulong step8 = (ulong)(twoP % 8UL);
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ulong step3 = (ulong)(twoP % 3UL);
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ulong step5 = (ulong)(twoP % 5UL);
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twoP.Mod10_8_5_3(out ulong step10, out ulong step8, out ulong step5, out ulong step3);
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step10 = step10.Mod10();
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// Allowed last-digit sets for q depending on last digit of M_p
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// lastIsSeven == true => allow {7,9}
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@@ -201,8 +201,8 @@ public ref struct GpuKernelLease(IDisposable limiter, GpuContextLease gpu, Kerne
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{
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ulong idx = (ulong)index.X;
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// residue automaton
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ulong step10 = ((exponent % 10UL) << 1) % 10UL;
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ulong r10 = q0m10 + (step10 * idx) % 10UL;
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ulong step10 = (exponent.Mod10() << 1).Mod10();
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ulong r10 = q0m10 + (step10 * idx).Mod10();
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r10 -= (r10 >= 10UL) ? 10UL : 0UL;
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bool shouldCheck = r10 != 5UL; // skip q ≡ 5 (mod 10); other residues handled by r8/r3/r5
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if (shouldCheck)
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@@ -358,7 +358,7 @@ public ref struct GpuKernelLease(IDisposable limiter, GpuContextLease gpu, Kerne
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ArrayView1D<ulong, Stride1D.Dense> smallPrimesPow2LastSeven)
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{
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ulong idx = (ulong)index.X;
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ulong r10 = ra.Q0M10 + (ra.Step10 * idx) % 10UL; r10 -= (r10 >= 10UL) ? 10UL : 0UL;
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ulong r10 = ra.Q0M10 + (ra.Step10 * idx).Mod10(); r10 -= (r10 >= 10UL) ? 10UL : 0UL;
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bool shouldCheck = r10 != 5UL;
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if (shouldCheck)
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{
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@@ -489,7 +489,7 @@ public ref struct GpuKernelLease(IDisposable limiter, GpuContextLease gpu, Kerne
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ResidueAutomatonArgs ra, ArrayView<int> found, ArrayView1D<uint, Stride1D.Dense> smallCycles)
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{
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ulong idx = (ulong)index.X;
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ulong r10 = ra.Q0M10 + (ra.Step10 * idx) % 10UL; r10 -= (r10 >= 10UL) ? 10UL : 0UL;
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ulong r10 = ra.Q0M10 + (ra.Step10 * idx).Mod10(); r10 -= (r10 >= 10UL) ? 10UL : 0UL;
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bool shouldCheck = r10 != 5UL;
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if (shouldCheck)
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{
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@@ -573,7 +573,7 @@ public ref struct GpuKernelLease(IDisposable limiter, GpuContextLease gpu, Kerne
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ResidueAutomatonArgs ra, ArrayView<int> found, ArrayView1D<uint, Stride1D.Dense> smallCycles)
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{
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ulong idx = (ulong)index.X;
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ulong r10 = ra.Q0M10 + (ra.Step10 * idx) % 10UL; r10 -= (r10 >= 10UL) ? 10UL : 0UL;
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ulong r10 = ra.Q0M10 + (ra.Step10 * idx).Mod10(); r10 -= (r10 >= 10UL) ? 10UL : 0UL;
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bool shouldCheck = r10 != 5UL;
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if (shouldCheck)
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{
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@@ -23,7 +23,7 @@ public class MersenneNumberIncrementalGpuTester(GpuKernelType kernelType, bool u
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var pow2Kernel = gpuLease.Pow2ModKernel;
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var incKernel = gpuLease.IncrementalKernel;
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ulong step10 = ((exponent % 10UL) << 1) % 10UL;
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ulong step10 = (exponent.Mod10() << 1).Mod10();
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ulong step8 = ((exponent & 7UL) << 1) & 7UL;
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ulong step3 = ((exponent % 3UL) << 1) % 3UL;
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ulong step5 = ((exponent % 5UL) << 1) % 5UL;
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@@ -7,68 +7,68 @@ public class MersenneNumberOrderGpuTester(GpuKernelType kernelType, bool useGpuO
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private readonly GpuKernelType _kernelType = kernelType;
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private readonly bool _useGpuOrder = useGpuOrder;
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public void Scan(ulong exponent, UInt128 twoP, bool lastIsSeven, UInt128 maxK, ref bool isPrime)
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{
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var gpuLease = GpuKernelPool.GetKernel(_useGpuOrder);
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var execution = gpuLease.EnterExecutionScope();
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var accelerator = gpuLease.Accelerator;
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var stream = gpuLease.Stream;
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int batchSize = GpuConstants.ScanBatchSize; // large batch improves GPU occupancy and avoids TDR
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UInt128 kStart = UInt128.One;
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ulong divMul = (ulong)((((UInt128)1 << 64) - UInt128.One) / exponent) + 1UL;
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byte last = lastIsSeven ? (byte)1 : (byte)0; // ILGPU kernels do not support bool parameters
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public void Scan(ulong exponent, UInt128 twoP, bool lastIsSeven, UInt128 maxK, ref bool isPrime)
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{
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var gpuLease = GpuKernelPool.GetKernel(_useGpuOrder);
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var execution = gpuLease.EnterExecutionScope();
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var accelerator = gpuLease.Accelerator;
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var stream = gpuLease.Stream;
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int batchSize = GpuConstants.ScanBatchSize; // large batch improves GPU occupancy and avoids TDR
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UInt128 kStart = UInt128.One;
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ulong divMul = (ulong)((((UInt128)1 << 64) - UInt128.One) / exponent) + 1UL;
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byte last = lastIsSeven ? (byte)1 : (byte)0; // ILGPU kernels do not support bool parameters
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var kernel = _kernelType switch
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{
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GpuKernelType.Pow2Mod => gpuLease.Pow2ModOrderKernel,
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_ => gpuLease.IncrementalOrderKernel,
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};
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var kernel = _kernelType switch
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{
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GpuKernelType.Pow2Mod => gpuLease.Pow2ModOrderKernel,
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_ => gpuLease.IncrementalOrderKernel,
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};
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var foundBuffer = accelerator.Allocate1D<int>(1);
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UInt128 exponent128 = exponent;
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exponent128.Mod10_8_5_3(out ulong exponentMod10, out ulong exponentMod8, out ulong exponentMod5, out ulong exponentMod3);
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ulong step10 = (exponentMod10 << 1) % 10UL;
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ulong step8 = (exponentMod8 << 1) & 7UL;
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ulong step3 = (exponentMod3 << 1) % 3UL;
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ulong step5 = (exponentMod5 << 1) % 5UL;
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try
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{
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UInt128 remaining;
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int currentSize;
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int found = 0;
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while (kStart <= maxK && Volatile.Read(ref isPrime))
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{
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remaining = maxK - kStart + 1UL;
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currentSize = remaining > (UInt128)batchSize ? batchSize : (int)remaining;
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foundBuffer.MemSetToZero();
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// Precompute residue automaton bases for this batch
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UInt128 q0 = twoP * kStart + 1UL;
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q0.Mod10_8_5_3(out ulong q0m10, out ulong q0m8, out ulong q0m5, out ulong q0m3);
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var kernelArgs = new ResidueAutomatonArgs(q0m10, step10, q0m8, step8, q0m3, step3, q0m5, step5);
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var foundBuffer = accelerator.Allocate1D<int>(1);
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UInt128 exponent128 = exponent;
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exponent128.Mod10_8_5_3(out ulong exponentMod10, out ulong exponentMod8, out ulong exponentMod5, out ulong exponentMod3);
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ulong step10 = (exponentMod10 << 1).Mod10();
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ulong step8 = (exponentMod8 << 1) & 7UL;
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ulong step3 = (exponentMod3 << 1) % 3UL;
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ulong step5 = (exponentMod5 << 1) % 5UL;
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try
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{
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UInt128 remaining;
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int currentSize;
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int found = 0;
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while (kStart <= maxK && Volatile.Read(ref isPrime))
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{
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remaining = maxK - kStart + 1UL;
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currentSize = remaining > (UInt128)batchSize ? batchSize : (int)remaining;
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foundBuffer.MemSetToZero();
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// Precompute residue automaton bases for this batch
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UInt128 q0 = twoP * kStart + 1UL;
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q0.Mod10_8_5_3(out ulong q0m10, out ulong q0m8, out ulong q0m5, out ulong q0m3);
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var kernelArgs = new ResidueAutomatonArgs(q0m10, step10, q0m8, step8, q0m3, step3, q0m5, step5);
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// Ensure device has small cycles table for early rejections in order kernels
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var smallCyclesView = GpuKernelPool.EnsureSmallCyclesOnDevice(accelerator);
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kernel(stream, currentSize, exponent, (GpuUInt128)twoP, (GpuUInt128)kStart, last, divMul,
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kernelArgs, foundBuffer.View, smallCyclesView);
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// Ensure device has small cycles table for early rejections in order kernels
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var smallCyclesView = GpuKernelPool.EnsureSmallCyclesOnDevice(accelerator);
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kernel(stream, currentSize, exponent, (GpuUInt128)twoP, (GpuUInt128)kStart, last, divMul,
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kernelArgs, foundBuffer.View, smallCyclesView);
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stream.Synchronize();
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foundBuffer.View.CopyToCPU(ref found, 1);
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if (found != 0)
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{
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Volatile.Write(ref isPrime, false);
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break;
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}
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stream.Synchronize();
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foundBuffer.View.CopyToCPU(ref found, 1);
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if (found != 0)
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{
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Volatile.Write(ref isPrime, false);
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break;
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}
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kStart += (UInt128)currentSize;
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}
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}
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finally
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{
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foundBuffer.Dispose();
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execution.Dispose();
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gpuLease.Dispose();
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}
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kStart += (UInt128)currentSize;
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}
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}
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finally
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{
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foundBuffer.Dispose();
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execution.Dispose();
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gpuLease.Dispose();
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}
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}
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}
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}
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@@ -24,7 +24,7 @@ public class MersenneNumberResidueGpuTester(bool useGpuOrder)
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UInt128 kStart = 1UL;
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byte last = lastIsSeven ? (byte)1 : (byte)0;
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var kernel = gpuLease.Pow2ModKernel;
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ulong step10 = ((exponent % 10UL) << 1) % 10UL;
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ulong step10 = (exponent.Mod10() << 1).Mod10();
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ulong step8 = ((exponent & 7UL) << 1) & 7UL;
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ulong step3 = ((exponent % 3UL) << 1) % 3UL;
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ulong step5 = ((exponent % 5UL) << 1) % 5UL;
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@@ -30,12 +30,12 @@ public sealed class MersenneResidueAutomaton
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_currentQ = _step + 1UL; // start at k = 1
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// init residues
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Mod10R = Mod10(_currentQ);
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Mod10R = _currentQ.Mod10();
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Mod8R = Mod8(_currentQ);
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Mod3R = Mod3(_currentQ);
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Mod5R = Mod5(_currentQ);
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_step10 = Mod10((ulong)(_step % 10UL));
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_step10 = _step.Mod10().Mod10();
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_step8 = (ulong)(_step & 7UL); // % 8
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_step3 = Mod3(_step);
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_step5 = Mod5(_step);
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@@ -72,21 +72,6 @@ public sealed class MersenneResidueAutomaton
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Mod5R = r5;
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}
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[MethodImpl(MethodImplOptions.AggressiveInlining)]
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private static ulong Mod10(UInt128 value)
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{
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// Split and fold under mod 10: 2^64 ≡ 6 (mod 10)
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ulong high = (ulong)(value >> 64);
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ulong low = (ulong)value;
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ulong highRem = Mod10(high);
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ulong lowRem = Mod10(low);
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ulong combined = lowRem + highRem * 6UL;
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return Mod10(combined);
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}
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[MethodImpl(MethodImplOptions.AggressiveInlining)]
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private static ulong Mod10(ulong value) => value % 10UL;
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[MethodImpl(MethodImplOptions.AggressiveInlining)]
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private static ulong Mod8(UInt128 value) => (ulong)value & 7UL;
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@@ -196,8 +181,8 @@ public sealed class Ending7Automaton
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[MethodImpl(MethodImplOptions.AggressiveInlining)]
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private static ulong AlignTo7(ulong start)
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{
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ulong r = start % 10UL;
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ulong add = (7UL + 10UL - r) % 10UL;
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ulong r = start.Mod10();
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ulong add = (7UL + 10UL - r).Mod10();
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return start + add;
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}
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@@ -59,7 +59,7 @@ public sealed class PrimeTester(bool useInternal = false)
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}
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else
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{
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if ((n % 10UL) == 1UL && SharesFactorWithMaxExponent(n))
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if (n.Mod10() == 1UL && SharesFactorWithMaxExponent(n))
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{
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result = false;
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}
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@@ -266,7 +266,7 @@ public sealed class PrimeTester(bool useInternal = false)
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return;
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}
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if ((n % 10UL) == 1UL)
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if (n.Mod10() == 1UL)
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{
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// Early reject special GCD heuristic with floor(log2 n)
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ulong m = 63UL - (ulong)ILGPU.Algorithms.XMath.LeadingZeroCount(n);
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@@ -5,109 +5,109 @@ namespace PerfectNumbers.Core;
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public static class PrimesGenerator
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{
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public static readonly uint[] SmallPrimes;
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public static readonly ulong[] SmallPrimesPow2;
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public static readonly uint[] SmallPrimesLastOne;
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public static readonly ulong[] SmallPrimesPow2LastOne;
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public static readonly uint[] SmallPrimesLastSeven;
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public static readonly ulong[] SmallPrimesPow2LastSeven;
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public static readonly uint[] SmallPrimes;
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public static readonly ulong[] SmallPrimesPow2;
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public static readonly uint[] SmallPrimesLastOne;
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public static readonly ulong[] SmallPrimesPow2LastOne;
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public static readonly uint[] SmallPrimesLastSeven;
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public static readonly ulong[] SmallPrimesPow2LastSeven;
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static PrimesGenerator()
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{
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BuildSmallPrimes(
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out SmallPrimes,
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out SmallPrimesPow2,
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out SmallPrimesLastOne,
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out SmallPrimesPow2LastOne,
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out SmallPrimesLastSeven,
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out SmallPrimesPow2LastSeven);
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}
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static PrimesGenerator()
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{
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BuildSmallPrimes(
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out SmallPrimes,
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out SmallPrimesPow2,
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out SmallPrimesLastOne,
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out SmallPrimesPow2LastOne,
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out SmallPrimesLastSeven,
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out SmallPrimesPow2LastSeven);
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}
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private static void BuildSmallPrimes(
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out uint[] all,
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out ulong[] allPow2,
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out uint[] lastOne,
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out ulong[] lastOnePow2,
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out uint[] lastSeven,
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out ulong[] lastSevenPow2)
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{
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uint target = PerfectNumberConstants.PrimesLimit;
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int targetInt = checked((int)target);
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all = new uint[targetInt];
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allPow2 = new ulong[targetInt];
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lastOne = new uint[targetInt];
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lastOnePow2 = new ulong[targetInt];
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lastSeven = new uint[targetInt];
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lastSevenPow2 = new ulong[targetInt];
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private static void BuildSmallPrimes(
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out uint[] all,
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out ulong[] allPow2,
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out uint[] lastOne,
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out ulong[] lastOnePow2,
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out uint[] lastSeven,
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out ulong[] lastSevenPow2)
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{
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uint target = PerfectNumberConstants.PrimesLimit;
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int targetInt = checked((int)target);
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all = new uint[targetInt];
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allPow2 = new ulong[targetInt];
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lastOne = new uint[targetInt];
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lastOnePow2 = new ulong[targetInt];
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lastSeven = new uint[targetInt];
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lastSevenPow2 = new ulong[targetInt];
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List<uint> primes = new(targetInt * 4 / 3 + 16);
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uint candidate = 2U;
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int allCount = 0;
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int lastOneCount = 0;
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int lastSevenCount = 0;
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List<uint> primes = new(targetInt * 4 / 3 + 16);
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uint candidate = 2U;
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int allCount = 0;
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int lastOneCount = 0;
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int lastSevenCount = 0;
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while (allCount < targetInt || lastOneCount < targetInt || lastSevenCount < targetInt)
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{
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bool isPrime = true;
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int primesCount = primes.Count;
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for (int i = 0; i < primesCount; i++)
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{
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uint p = primes[i];
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if (p * p > candidate)
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{
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break;
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}
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while (allCount < targetInt || lastOneCount < targetInt || lastSevenCount < targetInt)
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{
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bool isPrime = true;
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int primesCount = primes.Count;
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for (int i = 0; i < primesCount; i++)
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{
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uint p = primes[i];
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if (p * p > candidate)
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{
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break;
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}
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if (candidate % p == 0U)
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{
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isPrime = false;
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break;
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}
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}
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if (candidate % p == 0U)
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{
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isPrime = false;
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break;
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}
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}
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if (isPrime)
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{
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primes.Add(candidate);
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if (allCount < targetInt)
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{
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all[allCount] = candidate;
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allPow2[allCount] = checked((ulong)candidate * candidate);
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allCount++;
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}
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if (isPrime)
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{
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primes.Add(candidate);
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if (allCount < targetInt)
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{
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all[allCount] = candidate;
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allPow2[allCount] = checked((ulong)candidate * candidate);
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allCount++;
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}
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if (candidate != 2U)
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{
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if (lastOneCount < targetInt && IsAllowedForLastOne(candidate))
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{
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lastOne[lastOneCount] = candidate;
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lastOnePow2[lastOneCount] = checked((ulong)candidate * candidate);
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lastOneCount++;
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}
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if (candidate != 2U)
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{
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if (lastOneCount < targetInt && IsAllowedForLastOne(candidate))
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{
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lastOne[lastOneCount] = candidate;
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lastOnePow2[lastOneCount] = checked((ulong)candidate * candidate);
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lastOneCount++;
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}
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if (lastSevenCount < targetInt && IsAllowedForLastSeven(candidate))
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{
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||||
lastSeven[lastSevenCount] = candidate;
|
||||
lastSevenPow2[lastSevenCount] = checked((ulong)candidate * candidate);
|
||||
lastSevenCount++;
|
||||
}
|
||||
}
|
||||
}
|
||||
if (lastSevenCount < targetInt && IsAllowedForLastSeven(candidate))
|
||||
{
|
||||
lastSeven[lastSevenCount] = candidate;
|
||||
lastSevenPow2[lastSevenCount] = checked((ulong)candidate * candidate);
|
||||
lastSevenCount++;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
candidate = candidate == 2U ? 3U : candidate + 2U;
|
||||
}
|
||||
}
|
||||
candidate = candidate == 2U ? 3U : candidate + 2U;
|
||||
}
|
||||
}
|
||||
|
||||
[MethodImpl(MethodImplOptions.AggressiveInlining)]
|
||||
private static bool IsAllowedForLastOne(uint prime)
|
||||
{
|
||||
uint mod10 = prime % 10U;
|
||||
return mod10 == 1U || mod10 == 3U || mod10 == 9U || prime == 7U || prime == 11U;
|
||||
}
|
||||
[MethodImpl(MethodImplOptions.AggressiveInlining)]
|
||||
private static bool IsAllowedForLastOne(uint prime)
|
||||
{
|
||||
uint mod10 = prime % 10U;
|
||||
return mod10 == 1U || mod10 == 3U || mod10 == 9U || prime == 7U || prime == 11U;
|
||||
}
|
||||
|
||||
[MethodImpl(MethodImplOptions.AggressiveInlining)]
|
||||
private static bool IsAllowedForLastSeven(uint prime)
|
||||
{
|
||||
uint mod10 = prime % 10U;
|
||||
return mod10 == 3U || mod10 == 7U || mod10 == 9U || prime == 11U;
|
||||
}
|
||||
[MethodImpl(MethodImplOptions.AggressiveInlining)]
|
||||
private static bool IsAllowedForLastSeven(uint prime)
|
||||
{
|
||||
uint mod10 = prime % 10U;
|
||||
return mod10 == 3U || mod10 == 7U || mod10 == 9U || prime == 11U;
|
||||
}
|
||||
}
|
||||
@@ -215,11 +215,11 @@ public static class UInt128Extensions
|
||||
while (high != zero)
|
||||
{
|
||||
// 2^64 ≡ 6 (mod 10)
|
||||
result = (result + (ulong)high * 6UL) % 10UL;
|
||||
result = (result + (ulong)high * 6UL).Mod10();
|
||||
high >>= 64;
|
||||
}
|
||||
|
||||
return result % 10UL;
|
||||
return result.Mod10();
|
||||
}
|
||||
|
||||
[MethodImpl(MethodImplOptions.AggressiveInlining)]
|
||||
|
||||
Reference in new issue
Block a user