QuickSort C#を埋める.NETのソースコード

////  QuickSort C# .NET Sample Application//  Copyright 2001-2002 Microsoft Corporation. All rights reserved.////  MSDN ACADEMIC ALLIANCE [http://www.msdn.microsoft.com/academic]//  This sample is part of a vast collection of resources we developed for//  faculty members in K-12 and higher education. Visit the MSDN AA web site for more!//  The source code is provided "as is" without warranty.//// Import namespacesusing System;using System.Collections;using System.IO;// Declare namespacenamespace MsdnAA{    // Declare application class    class QuickSortApp    {        // Application initialization        static void Main (string[] szArgs)        {            // Print startup banner            Console.WriteLine ("
QuickSort C#.NET Sample Application");            Console.WriteLine ("Copyright (c)2001-2002 Microsoft Corporation. All rights reserved.
");            Console.WriteLine ("MSDN ACADEMIC ALLIANCE [http://www.msdnaa.net/]
");            // Describe program function            Console.WriteLine ("This example demonstrates the QuickSort algorithm by reading an input file,");            Console.WriteLine ("sorting its contents, and writing them to a new file.
");            // Prompt user for filenames            Console.Write ("Source: ");            string szSrcFile = Console.ReadLine ();            Console.Write ("Output: ");            string szDestFile = Console.ReadLine ();            // Read contents of source file            string szSrcLine;            ArrayList szContents = new ArrayList ();            FileStream fsInput = new FileStream (szSrcFile, FileMode.Open, FileAccess.Read);            StreamReader srInput = new StreamReader (fsInput);            while ((szSrcLine = srInput.ReadLine ()) != null)            {                // Append to array                szContents.Add (szSrcLine);            }            srInput.Close ();            fsInput.Close ();            // Pass to QuickSort function            QuickSort (szContents, 0, szContents.Count - 1);            // Write sorted lines            FileStream fsOutput = new FileStream (szDestFile, FileMode.Create, FileAccess.Write);            StreamWriter srOutput = new StreamWriter (fsOutput);            for (int nIndex = 0; nIndex < szContents.Count; nIndex++)            {                // Write line to output file                srOutput.WriteLine (szContents[nIndex]);            }            srOutput.Close ();            fsOutput.Close ();            // Report program success            Console.WriteLine ("
The sorted lines have been written to the output file.

");        }        // QuickSort implementation        private static void QuickSort (ArrayList szArray, int nLower, int nUpper)        {            // Check for non-base case            if (nLower < nUpper)            {                // Split and sort partitions                int nSplit = Partition (szArray, nLower, nUpper);                QuickSort (szArray, nLower, nSplit - 1);                QuickSort (szArray, nSplit + 1, nUpper);            }        }        // QuickSort partition implementation        private static int Partition (ArrayList szArray, int nLower, int nUpper)        {            // Pivot with first element            int nLeft = nLower + 1;            string szPivot = (string) szArray[nLower];            int nRight = nUpper;            // Partition array elements            string szSwap;            while (nLeft <= nRight)            {                // Find item out of place                while (nLeft <= nRight && ((string) szArray[nLeft]).CompareTo (szPivot) <= 0)                    nLeft = nLeft + 1;                while (nLeft <= nRight && ((string) szArray[nRight]).CompareTo (szPivot) > 0)                    nRight = nRight - 1;                // Swap values if necessary                if (nLeft < nRight)                {                    szSwap = (string) szArray[nLeft];                    szArray[nLeft] = szArray[nRight];                    szArray[nRight] = szSwap;                    nLeft = nLeft + 1;                    nRight = nRight - 1;                }            }            // Move pivot element            szSwap = (string) szArray[nLower];            szArray[nLower] = szArray[nRight];            szArray[nRight] = szSwap;            return nRight;        }    }}