Code:
/ FXUpdate3074 / FXUpdate3074 / 1.1 / untmp / whidbey / QFE / ndp / fx / src / Xml / System / Xml / Bits.cs / 1 / Bits.cs
//------------------------------------------------------------------------------ //// Copyright (c) Microsoft Corporation. All rights reserved. // //[....] //----------------------------------------------------------------------------- namespace System.Xml { using System; using System.Diagnostics; ////// Contains static utility methods used to manipulate bits in a word. /// internal static class Bits { private static readonly uint MASK_0101010101010101 = 0x55555555; private static readonly uint MASK_0011001100110011 = 0x33333333; private static readonly uint MASK_0000111100001111 = 0x0f0f0f0f; private static readonly uint MASK_0000000011111111 = 0x00ff00ff; private static readonly uint MASK_1111111111111111 = 0x0000ffff; ////// Returns the number of 1 bits in an unsigned integer. Counts bits by divide-and-conquer method, /// first computing 16 2-bit counts, then 8 4-bit counts, then 4 8-bit counts, then 2 16-bit counts, /// and finally 1 32-bit count. /// public static int Count(uint num) { num = (num & MASK_0101010101010101) + ((num >> 1) & MASK_0101010101010101); num = (num & MASK_0011001100110011) + ((num >> 2) & MASK_0011001100110011); num = (num & MASK_0000111100001111) + ((num >> 4) & MASK_0000111100001111); num = (num & MASK_0000000011111111) + ((num >> 8) & MASK_0000000011111111); num = (num & MASK_1111111111111111) + (num >> 16); return (int) num; } ////// Returns true if the unsigned integer has exactly one bit set. /// public static bool ExactlyOne(uint num) { return num != 0 && (num & (num - 1)) == 0; } ////// Returns true if the unsigned integer has more than one bit set. /// public static bool MoreThanOne(uint num) { return (num & (num - 1)) != 0; } ////// Clear the least significant bit that is set and return the result. /// public static uint ClearLeast(uint num) { return num & (num - 1); } ////// Compute the 1-based position of the least sigificant bit that is set, and return it (return 0 if no bits are set). /// (e.g. 0x1001100 will return 3, since the 3rd bit is set). /// public static int LeastPosition(uint num) { if (num == 0) return 0; return Count(num ^ (num - 1)); } } } // File provided for Reference Use Only by Microsoft Corporation (c) 2007. // Copyright (c) Microsoft Corporation. All rights reserved.
Link Menu
This book is available now!
Buy at Amazon US or
Buy at Amazon UK
- SerialErrors.cs
- DocumentGrid.cs
- SqlConnectionPoolGroupProviderInfo.cs
- ToolStrip.cs
- ScanQueryOperator.cs
- CompilerWrapper.cs
- Thickness.cs
- SystemDropShadowChrome.cs
- AutomationElementIdentifiers.cs
- AssemblyLoader.cs
- Timer.cs
- EntityParameterCollection.cs
- DataReceivedEventArgs.cs
- UnicodeEncoding.cs
- InputBuffer.cs
- WrappedIUnknown.cs
- AbstractExpressions.cs
- FormsAuthenticationEventArgs.cs
- EdgeProfileValidation.cs
- OleDbConnectionFactory.cs
- ServiceAuthorizationElement.cs
- DataGridColumn.cs
- TripleDES.cs
- ForeignKeyConstraint.cs
- Transactions.cs
- BaseProcessor.cs
- ImportContext.cs
- PageAsyncTask.cs
- WebPart.cs
- storepermissionattribute.cs
- SourceSwitch.cs
- ToolboxComponentsCreatingEventArgs.cs
- EdmRelationshipRoleAttribute.cs
- SubqueryRules.cs
- parserscommon.cs
- DockPatternIdentifiers.cs
- DataGridViewCellCollection.cs
- GlyphInfoList.cs
- DetailsViewRow.cs
- ToolStripDropDownButton.cs
- SecUtil.cs
- SpeakCompletedEventArgs.cs
- securitycriticaldata.cs
- BridgeDataRecord.cs
- GetIsBrowserClientRequest.cs
- SingletonConnectionReader.cs
- fixedPageContentExtractor.cs
- NumberFormatter.cs
- ImportOptions.cs
- ListItemCollection.cs
- CharEntityEncoderFallback.cs
- Trace.cs
- Wizard.cs
- XmlSchemaAttributeGroup.cs
- TreeWalkHelper.cs
- TextModifierScope.cs
- TextBoxView.cs
- ProcessModelSection.cs
- SQLDateTimeStorage.cs
- HelpKeywordAttribute.cs
- CheckBoxList.cs
- RotateTransform.cs
- WindowsScrollBar.cs
- Regex.cs
- HotSpotCollection.cs
- ProviderConnectionPoint.cs
- MailDefinition.cs
- TypeDescriptionProvider.cs
- LocationUpdates.cs
- CanExpandCollapseAllConverter.cs
- streamingZipPartStream.cs
- XmlSchemaNotation.cs
- SqlClientWrapperSmiStream.cs
- StrongNameMembershipCondition.cs
- PersianCalendar.cs
- DateTimeStorage.cs
- IncrementalReadDecoders.cs
- ProxyFragment.cs
- AmbientValueAttribute.cs
- BaseResourcesBuildProvider.cs
- BufferBuilder.cs
- SafeNativeMethodsMilCoreApi.cs
- _Events.cs
- CompoundFileDeflateTransform.cs
- WebSysDisplayNameAttribute.cs
- PasswordTextContainer.cs
- ObjectFactoryCodeDomTreeGenerator.cs
- MarkupWriter.cs
- RelationshipConverter.cs
- EncoderNLS.cs
- CodeMemberMethod.cs
- ExceptQueryOperator.cs
- DataGridViewImageColumn.cs
- GroupItemAutomationPeer.cs
- GestureRecognitionResult.cs
- CollectionViewProxy.cs
- RichTextBox.cs
- DataSourceXmlAttributeAttribute.cs
- AnnotationAdorner.cs
- UIAgentInitializationException.cs