C# HashSet类代码示例

        private static void SwapParameterTypes(MethodDefinition method,
            TypeDefinition targetDependency,
            TypeReference interfaceType,
            HashSet<MethodReference> modifiedMethods)
        {
            if (method.IsAbstract || !method.HasBody)
                return;

            bool modified = false;
            var parameters = method.Parameters.Cast<ParameterDefinition>();
            foreach (var parameter in parameters)
            {
                var parameterType = parameter.ParameterType;
                if (parameterType != targetDependency)
                    continue;

                parameter.ParameterType = interfaceType;
                modified = true;
            }

            if (!modified)
                return;

            modifiedMethods.Add(method);
        }

 public static H3.Cell[] CalcCells2( Sphere[] mirrors, H3.Cell[] cells, Settings settings )
 {
     HashSet<Vector3D> completedCellIds = new HashSet<Vector3D>( cells.Select( c => c.ID ).ToArray() );
     List<H3.Cell> completedCells = new List<H3.Cell>( cells );
     ReflectCellsRecursive2( mirrors, cells, settings, completedCells, completedCellIds );
     return completedCells.ToArray();
 }

        private void AssignConnectors(DialogueEntry entry, Conversation conversation, HashSet<string> alreadyConnected, HashSet<int> entriesVisited, int level)
        {
            // Sanity check to prevent infinite recursion:
            if (level > 10000) return;

            // Set non-connectors:
            foreach (Link link in entry.outgoingLinks) {
                if (link.originConversationID == link.destinationConversationID) {
                    string destination = string.Format("{0}.{1}", link.destinationConversationID, link.destinationDialogueID);
                    if (alreadyConnected.Contains(destination)) {
                        link.isConnector = true;
                    } else {
                        link.isConnector = false;
                        alreadyConnected.Add(destination);
                    }
                }
            }

            // Then process each child:
            foreach (Link link in entry.outgoingLinks) {
                if (link.originConversationID == link.destinationConversationID) {
                    if (!entriesVisited.Contains(link.destinationDialogueID)) {
                        entriesVisited.Add(link.destinationDialogueID);
                        var childEntry = conversation.GetDialogueEntry(link.destinationDialogueID);
                        if (childEntry != null) {
                            AssignConnectors(childEntry, conversation, alreadyConnected, entriesVisited, level + 1);
                        }
                    }
                }
            }
        }

        public static void Write(TextWriter writer, IEnumerable<Dictionary<string, string>> records)
        {
            if (records == null) return; //AOT

            var allKeys = new HashSet<string>();
            var cachedRecords = new List<IDictionary<string, string>>();

            foreach (var record in records)
            {
                foreach (var key in record.Keys)
                {
                    if (!allKeys.Contains(key))
                    {
                        allKeys.Add(key);
                    }
                }
                cachedRecords.Add(record);
            }

            var headers = allKeys.OrderBy(key => key).ToList();
            if (!CsvConfig<Dictionary<string, string>>.OmitHeaders)
            {
                WriteRow(writer, headers);
            }
            foreach (var cachedRecord in cachedRecords)
            {
                var fullRecord = headers.ConvertAll(header => 
                    cachedRecord.ContainsKey(header) ? cachedRecord[header] : null);
                WriteRow(writer, fullRecord);
            }
        }

        /// <summary>
        /// Locates the changes between the prior and post state of the modules..
        /// </summary>
        /// <param name="modules_prior">List of the available modules prior to the update.</param>
        /// <param name="modules_post">List of the available modules after the update.</param>
        private void PrintChanges(List<CkanModule> modules_prior, List<CkanModule> modules_post)
        {
            var prior = new HashSet<CkanModule>(modules_prior, new NameComparer());
            var post = new HashSet<CkanModule>(modules_post, new NameComparer());


            var added = new HashSet<CkanModule>(post.Except(prior, new NameComparer()));
            var removed = new HashSet<CkanModule>(prior.Except(post, new NameComparer()));


            var unchanged = post.Intersect(prior);//Default compare includes versions
            var updated = post.Except(unchanged).Except(added).Except(removed).ToList();

            // Print the changes.
            user.RaiseMessage("Found {0} new modules, {1} removed modules and {2} updated modules.", added.Count(), removed.Count(), updated.Count());

            if (added.Count > 0)
            {
                PrintModules("New modules [Name (CKAN identifier)]:", added);
            }

            if (removed.Count > 0)
            {
                PrintModules("Removed modules [Name (CKAN identifier)]:", removed);
            }

            if (updated.Count > 0)
            {
                PrintModules("Updated modules [Name (CKAN identifier)]:", updated);
            }
        }

 internal CoordinatorScratchpad(Type elementType)
 {
     _elementType = elementType;
     _nestedCoordinatorScratchpads = new List<CoordinatorScratchpad>();
     _expressionWithErrorHandlingMap = new Dictionary<Expression, Expression>();
     _inlineDelegates = new HashSet<LambdaExpression>();
 }

            internal AnalysisQueue(VsProjectAnalyzer analyzer) {
                _workEvent = new AutoResetEvent(false);
                _cancel = new CancellationTokenSource();
                _analyzer = analyzer;

                // save the analysis once it's ready, but give us a little time to be
                // initialized and start processing stuff...
                _lastSave = DateTime.Now - _SaveAnalysisTime + TimeSpan.FromSeconds(10);

                _queue = new List<IAnalyzable>[PriorityCount];
                for (int i = 0; i < PriorityCount; i++) {
                    _queue[i] = new List<IAnalyzable>();
                }
                _enqueuedGroups = new HashSet<IGroupableAnalysisProject>();

                _workThread = new Thread(Worker);
                _workThread.Name = "Node.js Analysis Queue";
                _workThread.Priority = ThreadPriority.BelowNormal;
                _workThread.IsBackground = true;

                // start the thread, wait for our synchronization context to be created
                using (AutoResetEvent threadStarted = new AutoResetEvent(false)) {
                    _workThread.Start(threadStarted);
                    threadStarted.WaitOne();
                }
            }

        public User(StateManager stateMgr, API.Geo.World world)
        {
            this.mStateMgr = stateMgr;
            this.mWorld = world;
            this.mTimeSinceGUIOpen = new Timer();

            this.mCameraMan = null;
            this.IsAllowedToMoveCam = true;
            this.IsFreeCamMode = true;
            Camera cam = this.mStateMgr.Camera;
            cam.Position = new Vector3(-203, 633, -183);
            cam.Orientation = new Quaternion(0.3977548f, -0.1096644f, -0.8781486f, -0.2421133f);
            this.mCameraMan = new CameraMan(cam);
            this.mSelectedAllies = new HashSet<VanillaNonPlayer>();
            this.mRandom = new Random();

            this.mFigures = new MOIS.KeyCode[10];
            for (int i = 0; i < 9; i++)
                this.mFigures[i] = (MOIS.KeyCode)System.Enum.Parse(typeof(MOIS.KeyCode), "KC_" + (i + 1));
            this.mFigures[9] = MOIS.KeyCode.KC_0;

            this.mWireCube = this.mStateMgr.SceneMgr.RootSceneNode.CreateChildSceneNode();
            this.mWireCube.AttachObject(StaticRectangle.CreateRectangle(this.mStateMgr.SceneMgr, Vector3.UNIT_SCALE * Cst.CUBE_SIDE));
            this.mWireCube.SetVisible(false);

            this.Inventory = new Inventory(10, 4, new int[] { 3, 0, 1, 2 }, true);
        }

        private bool m_useStrict; //= false;

        #endregion Fields

        #region Constructors

        protected JsActivationObject(JsActivationObject parent, JsSettings codeSettings)
        {
            m_isKnownAtCompileTime = true;
            m_useStrict = false;
            m_settings = codeSettings;

            Parent = parent;
            NameTable = new Dictionary<string, JsVariableField>();
            ChildScopes = new List<JsActivationObject>();

            // if our parent is a scope....
            if (parent != null)
            {
                // add us to the parent's list of child scopes
                parent.ChildScopes.Add(this);

                // if the parent is strict, so are we
                UseStrict = parent.UseStrict;
            }

            // create the two lists of declared items for this scope
            ScopeLookups = new HashSet<JsLookup>();
            VarDeclaredNames = new HashSet<IJsNameDeclaration>();
            LexicallyDeclaredNames = new HashSet<IJsNameDeclaration>();

            GhostedCatchParameters = new HashSet<JsParameterDeclaration>();
            GhostedFunctions = new HashSet<JsFunctionObject>();
        }

		public override void OnUpdateList ()
		{
			base.OnUpdateList ();
			StackFrame frame = DebuggingService.CurrentFrame;
			
			if (frame == null || !FrameEquals (frame, lastFrame)) {
				tree.ClearExpressions ();
				lastExpressions = null;
			}
			lastFrame = frame;
			
			if (frame == null)
				return;
			
			//FIXME: tree should use the local refs rather than expressions. ATM we exclude items without names
			var expr = new HashSet<string> (frame.GetAllLocals ().Select (i => i.Name)
				.Where (n => !string.IsNullOrEmpty (n) && n != "?"));
			
			//add expressions not in tree already, remove expressions that are longer valid
			if (lastExpressions != null) {
				foreach (string rem in lastExpressions.Except (expr))
					tree.RemoveExpression (rem);
				foreach (string rem in expr.Except (lastExpressions))
					tree.AddExpression (rem);
			} else {
				tree.AddExpressions (expr);
			}
			
			lastExpressions = expr;
		}

        public static IEnumerable<string> GetAllStyleSheets(string searchFrom, IEnumerable<string> allowedExtensions)
        {
            var project = ProjectHelpers.GetProject(searchFrom);
            var projectPath = project.Properties.Item("FullPath").Value.ToString();
            var projectUri = new Uri(projectPath, UriKind.Absolute);
            var fileNames = new HashSet<string>();
            var projectDir = Path.GetDirectoryName(projectPath);

            if (projectDir == null)
            {
                return new string[0];
            }

            foreach (var extension in allowedExtensions)
            {
                var matchingFiles = Directory.GetFiles(projectDir, "*" + extension, SearchOption.AllDirectories);

                foreach (var file in matchingFiles)
                {
                    var mappedFile = GetStyleSheetFileForUrl(file, project, projectUri);

                    if (mappedFile != null)
                    {
                        fileNames.Add(mappedFile);
                    }
                }
            }

            return fileNames;
        }

        private void CollectEntities(int addr, Dictionary<int, Entity> list)
        {
            int num = addr;
            addr = M.ReadInt(addr + 4);
            var hashSet = new HashSet<int>();
            var queue = new Queue<int>();
            queue.Enqueue(addr);
            while (queue.Count > 0)
            {
                int nextAddr = queue.Dequeue();
                if (hashSet.Contains(nextAddr))
                    continue;

                hashSet.Add(nextAddr);
                if (M.ReadByte(nextAddr + 21) == 0 && nextAddr != num && nextAddr != 0)
                {
                    int key = M.ReadInt(nextAddr + 12);
                    if (!list.ContainsKey(key))
                    {
                        int address = M.ReadInt(nextAddr + 16);
                        var entity = base.GetObject<Entity>(address);
                        list.Add(key, entity);
                    }
                    queue.Enqueue(M.ReadInt(nextAddr));
                    queue.Enqueue(M.ReadInt(nextAddr + 8));
                }
            }
        }

 private IList<string> DFS(string s, HashSet<string> dict, Dictionary<string, IList<string>> map){
     IList<string> matches = new List<string>();
     if(s==""){  //Base Case
         matches.Add("");
         return matches;
     }
     
     if(map.ContainsKey(s)) //if s is already in the map, directly return its value
         return map[s];
         
     int len = s.Length;
     for(int i=1;i<s.Length+1;i++){
         string prev = s.Substring(0,i);
         if(dict.Contains(prev)){ //if prev is in the dict
             IList<string> postMatches = DFS(s.Substring(i,len-i),dict,map);
             foreach(string sentence in postMatches){
                 if(sentence=="") //if s.Substring(i,len) is empty
                     matches.Add(prev);
                 else
                     matches.Add(prev+" "+sentence);
             }
             
         }
     }
     map.Add(s, matches); //after get all matches for s, put the entry into map.
     return matches;
 }

        private static IEnumerable<long> Eratostenes()
        {
            const int max = 2000000;
            var primes = new List<long>();
            var crossedOff = new HashSet<long>();

            long candidate = 1;

            while (candidate < max)
            {
                candidate++;

                if (crossedOff.Contains(candidate))
                {
                    continue;
                }

                primes.Add(candidate);

                // remove multiples of candidate
                for (var i = candidate; i < max + 1; i += candidate)
                {
                    crossedOff.Add(i);
                }
            }

            return primes.ToArray();
        }

    static void Main()
    {
        InitializeWordsByChar();

        int textLinesCount = int.Parse(Console.ReadLine().ToLower());
        for (int i = 0; i < textLinesCount; i++)
        {
            GetWords(Console.ReadLine().ToLower());
        }

        int wordsCount = int.Parse(Console.ReadLine());
        for (int i = 0; i < wordsCount; i++)
        {
            string word = Console.ReadLine();
            string wordLowerCase = word.ToLower();
            HashSet<string> currentWords = new HashSet<string>();
            currentWords.UnionWith(wordsByChar[wordLowerCase[0]]);
            for (int j = 1; j < wordLowerCase.Length; j++)
            {
                currentWords.IntersectWith(wordsByChar[wordLowerCase[j]]);
            }

            Console.WriteLine("{0} -> {1}", word, currentWords.Count);
        }
    }