Java数据结构与算法--高级排序

（1）快速排序

 /**
  *
  * @author sunnyykn
  */
 class ArrayIns
 {
     private long[] theArray;            //ref to array theArray
     private int nElems;                 //number of data items
     public ArrayIns(int max)           //constructor
     {
         theArray = new long[max];       //create the array
         nElems = 0;                     //no items yet
     }
     public void insert(long value)     //put element into array
     {
         theArray[nElems] = value;       //insert it
         nElems ++;                      //increment size
     }
     public void display()
     {
         System.out.print("A = ");
         for(int j = 0;j < nElems;j ++)
             System.out.print(theArray[j] + " ");
         System.out.println("");
     }
     public void quickSort()
     {
         recQuickSort(0,nElems - 1);
     }
     public void recQuickSort(int left,int right)
     {
         int size = right - left + 1;
         if(size < 10)                                   //insertion sort if small
             insertionSort(left,right);
         else                                            //quicksort if large
         {
             long median = medianOf3(left,right);
             int partition = partitionIt(left,right,median);
             recQuickSort(left,partition - 1);
             recQuickSort(partition + 1,right);
         }
     }
     public long medianOf3(int left,int right)
     {
         int center = (left + right)/2;
         if( theArray[left] > theArray[center] )     //order left & center
             swap(left,right);
         if( theArray[left] > theArray[right] )      //order left & right
             swap(left,right);
         if( theArray[center] > theArray[right] )    //order center & right
             swap(center,right);
         swap(center,right - 1);
         return theArray[right - 1];
     }
     public void swap(int dex1,int dex2)
     {
         long temp = theArray[dex1];
         theArray[dex1] = theArray[dex2];
         theArray[dex2] = temp;
     }
     public int partitionIt(int left,int right,long pivot)
     {
         int leftPtr = left;
         int rightPtr = right;
         while(true)
         {
             while( theArray[++ leftPtr] < pivot );
             while( theArray[-- rightPtr] > pivot );
             if(leftPtr >= rightPtr)
                 break;
             else
                 swap(leftPtr,rightPtr);
         }
         swap(leftPtr,right - 1);
         return leftPtr;
     }
     public void insertionSort(int left,int right)
     {
         int in,out;
         for(out = left + 1;out <= right;out ++)
         {
             long temp = theArray[out];
             in = out;
             while(in > left && theArray[in - 1] >= temp)
             {
                 theArray[in] = theArray[in - 1];
                 -- in;
             }
             theArray[in] = temp;
         }
     }
 }
 class QuickSortApp
 {
     public static void main(String[] args)
     {
         int maxSize = 50;               //array size
         ArrayIns arr;                   //reference to array
         arr = new ArrayIns(maxSize);    //create the array
         for(int j = 0;j < maxSize;j ++) //fill array with
         {                               //random numbers
             long n = (int)(java.lang.Math.random()*99);
             arr.insert(n);
         }
         arr.display();                  //display items
         arr.quickSort();                //quicksort them
         arr.display();                  //display them again
     }
 }

（2）希尔排序

public void shellSort{
  int inner, outer;
  long temp;
  int h = 1;
  while(h <= nElems/3)
   h = h*3 + 1;
  while(h > 0){
   for(outer = h; outer < nElems; outer++){
    temp = theArray[outer];
    inner = outer;
    while(inner > h - 1 && theArray[inner - h] >= temp){
     theArray[inner] = theArray[inner - h];
     inner -= h;
    }
    theArray[inner] = temp;
   }
   h = (h - 1)/3;
  }
 }