各种排序算法java实现

Java代码
package org.rut.util.algorithm.support;  
   
import org.rut.util.algorithm.SortUtil;  
/** 
* @author treeroot 
* @since 2010-11-22 
* @version 1.0 
*/ 
public class InsertSort implements SortUtil.Sort{  
   
    /* (non-Javadoc) 
     * @see org.rut.util.algorithm.SortUtil.Sort#sort(int[]) 
     */ 
    public void sort(int[] data) {  
        int temp;  
        for(int i=1;i<data.length;i++){  
            for(int j=i;(j>0)&&(data[j]<data[j-1]);j--){  
                SortUtil.swap(data,j,j-1);  
            }  
        }          
    }  
   
}  
 
 
冒泡排序:  
   
package org.rut.util.algorithm.support;  
   
import org.rut.util.algorithm.SortUtil;  
   
/** 
* @author treeroot 
* @since 2010-11-22 
* @version 1.0 
*/ 
public class BubbleSort implements SortUtil.Sort{  
   
    /* (non-Javadoc) 
     * @see org.rut.util.algorithm.SortUtil.Sort#sort(int[]) 
     */ 
    public void sort(int[] data) {  
        int temp;  
        for(int i=0;i<data.length;i++){  
            for(int j=data.length-1;j>i;j--){  
                if(data[j]<data[j-1]){  
                    SortUtil.swap(data,j,j-1);  
                }  
            }  
        }  
    }  
   
}  
   
 
选择排序:  
   
package org.rut.util.algorithm.support;  
   
import org.rut.util.algorithm.SortUtil;  
   
/** 
* @author treeroot 
* @since 2010-11-22 
* @version 1.0 
*/ 
public class SelectionSort implements SortUtil.Sort {  
   
    /* 
     * (non-Javadoc) 
     *  
     * @see org.rut.util.algorithm.SortUtil.Sort#sort(int[]) 
     */ 
    public void sort(int[] data) {  
        int temp;  
        for (int i = 0; i >< data.length; i++) {  
            int lowIndex = i;  
            for (int j = data.length - 1; j > i; j--) {  
                if (data[j] < data[lowIndex]) {  
                    lowIndex = j;  
                }  
            }  
            SortUtil.swap(data,i,lowIndex);  
        }  
    }  
   
}  
   
 
Shell排序:  
   
package org.rut.util.algorithm.support;  
   
import org.rut.util.algorithm.SortUtil;  
   
/** 
* @author treeroot 
* @since 2010-11-22 
* @version 1.0 
*/ 
public class ShellSort implements SortUtil.Sort{  
   
    /* (non-Javadoc) 
     * @see org.rut.util.algorithm.SortUtil.Sort#sort(int[]) 
     */ 
    public void sort(int[] data) {  
        for(int i=data.length/2;i>2;i/=2){  
            for(int j=0;j<i;j++){  
                insertSort(data,j,i);  
            }  
        }  
        insertSort(data,0,1);  
    }  
   
    /** 
     * @param data 
     * @param j 
     * @param i 
     */ 
    private void insertSort(int[] data, int start, int inc) {  
        int temp;  
        for(int i=start+inc;i<data.length;i+=inc){  
            for(int j=i;(j>=inc)&&(data[j]<data[j-inc]);j-=inc){  
                SortUtil.swap(data,j,j-inc);  
            }  
        }  
    }  
   
}  
   
 
快速排序:  
   
package org.rut.util.algorithm.support;  
   
import org.rut.util.algorithm.SortUtil;  
   
/** 
* @author treeroot 
* @since 2010-11-22 
* @version 1.0 
*/ 
public class QuickSort implements SortUtil.Sort{  
   
    /* (non-Javadoc) 
     * @see org.rut.util.algorithm.SortUtil.Sort#sort(int[]) 
     */ 
    public void sort(int[] data) {  
        quickSort(data,0,data.length-1);          
    }  
    private void quickSort(int[] data,int i,int j){  
        int pivotIndex=(i+j)/2;  
        //swap  
        SortUtil.swap(data,pivotIndex,j);  
          
        int k=partition(data,i-1,j,data[j]);  
        SortUtil.swap(data,k,j);  
        if((k-i)>1) quickSort(data,i,k-1);  
        if((j-k)>1) quickSort(data,k+1,j);  
          
    }  
    /** 
     * @param data 
     * @param i 
     * @param j 
     * @return 
     */ 
    private int partition(int[] data, int l, int r,int pivot) {  
        do{  
           while(data[++l]<pivot);  
           while((r!=0)&&data[--r]>pivot);  
           SortUtil.swap(data,l,r);  
        }  
        while(l<r);  
        SortUtil.swap(data,l,r);          
        return l;  
    }  
   
}  
 
 
改进后的快速排序:  
   
package org.rut.util.algorithm.support;  
   
import org.rut.util.algorithm.SortUtil;  
   
/** 
* @author treeroot 
* @since 2010-11-22 
* @version 1.0 
*/ 
public class ImprovedQuickSort implements SortUtil.Sort {  
   
    private static int MAX_STACK_SIZE=4096;  
    private static int THRESHOLD=10;  
    /* (non-Javadoc) 
     * @see org.rut.util.algorithm.SortUtil.Sort#sort(int[]) 
     */ 
    public void sort(int[] data) {  
        int[] stack=new int[MAX_STACK_SIZE];  
          
        int top=-1;  
        int pivot;  
        int pivotIndex,l,r;  
          
        stack[++top]=0;  
        stack[++top]=data.length-1;  
          
        while(top>0){  
            int j=stack[top--];  
            int i=stack[top--];  
              
            pivotIndex=(i+j)/2;  
            pivot=data[pivotIndex];  
              
            SortUtil.swap(data,pivotIndex,j);  
              
            //partition  
            l=i-1;  
            r=j;  
            do{  
                while(data[++l]<pivot);  
                while((r!=0)&&(data[--r]>pivot));  
                SortUtil.swap(data,l,r);  
            }  
            while(l<r);  
            SortUtil.swap(data,l,r);  
            SortUtil.swap(data,l,j);  
              
            if((l-i)>THRESHOLD){  
                stack[++top]=i;  
                stack[++top]=l-1;  
            }  
            if((j-l)>THRESHOLD){  
                stack[++top]=l+1;  
                stack[++top]=j;  
            }  
              
        }  
        //new InsertSort().sort(data);  
        insertSort(data);  
    }  
    /** 
     * @param data 
     */ 
    private void insertSort(int[] data) {  
        int temp;  
        for(int i=1;i<data.length;i++){  
            for(int j=i;(j>0)&&(data[j]<data[j-1]);j--){  
                SortUtil.swap(data,j,j-1);  
            }  
        }         
    }  
   
}  
   
 
归并排序:  
   
package org.rut.util.algorithm.support;  
   
import org.rut.util.algorithm.SortUtil;  
   
/** 
* @author treeroot 
* @since 2010-11-22 
* @version 1.0 
*/ 
public class MergeSort implements SortUtil.Sort{  
   
    /* (non-Javadoc) 
     * @see org.rut.util.algorithm.SortUtil.Sort#sort(int[]) 
     */ 
    public void sort(int[] data) {  
        int[] temp=new int[data.length];  
        mergeSort(data,temp,0,data.length-1);  
    }  
      
    private void mergeSort(int[] data,int[] temp,int l,int r){  
        int mid=(l+r)/2;  
        if(l==r) return ;  
        mergeSort(data,temp,l,mid);  
        mergeSort(data,temp,mid+1,r);  
        for(int i=l;i<=r;i++){  
            temp[i]=data[i];  
        }  
        int i1=l;  
        int i2=mid+1;  
        for(int cur=l;cur<=r;cur++){  
            if(i1==mid+1)  
                data[cur]=temp[i2++];  
            else if(i2>r)  
                data[cur]=temp[i1++];  
            else if(temp[i1]<temp[i2])  
                data[cur]=temp[i1++];  
            else 
                data[cur]=temp[i2++];              
        }  
    }  
   
}  
   
 
改进后的归并排序:  
   
package org.rut.util.algorithm.support;  
   
import org.rut.util.algorithm.SortUtil;  
   
/** 
* @author treeroot 
* @since 2010-11-22 
* @version 1.0 
*/ 
public class ImprovedMergeSort implements SortUtil.Sort {  
   
    private static final int THRESHOLD = 10;  
   
    /* 
     * (non-Javadoc) 
     *  
     * @see org.rut.util.algorithm.SortUtil.Sort#sort(int[]) 
     */ 
    public void sort(int[] data) {  
        int[] temp=new int[data.length];  
        mergeSort(data,temp,0,data.length-1);  
    }  
   
    private void mergeSort(int[] data, int[] temp, int l, int r) {  
        int i, j, k;  
        int mid = (l + r) / 2;  
        if (l == r)  
            return;  
        if ((mid - l) >= THRESHOLD)  
            mergeSort(data, temp, l, mid);  
        else 
            insertSort(data, l, mid - l + 1);  
        if ((r - mid) > THRESHOLD)  
            mergeSort(data, temp, mid + 1, r);  
        else 
            insertSort(data, mid + 1, r - mid);  
   
        for (i = l; i <= mid; i++) {  
            temp[i] = data[i];  
        }  
        for (j = 1; j <= r - mid; j++) {  
            temp[r - j + 1] = data[j + mid];  
        }  
        int a = temp[l];  
        int b = temp[r];  
        for (i = l, j = r, k = l; k <= r; k++) {  
            if (a < b) {  
                data[k] = temp[i++];  
                a = temp[i];  
            } else {  
                data[k] = temp[j--];  
                b = temp[j];  
            }  
        }  
    }  
   
    /** 
     * @param data 
     * @param l 
     * @param i 
     */ 
    private void insertSort(int[] data, int start, int len) {  
        for(int i=start+1;i<start+len;i++){  
            for(int j=i;(j>start) && data[j]<data[j-1];j--){  
                SortUtil.swap(data,j,j-1);  
            }  
        }  
    }  
   
}  
 
 
堆排序:  
   
package org.rut.util.algorithm.support;  
   
import org.rut.util.algorithm.SortUtil;  
   
/** 
* @author treeroot 
* @since 2010-11-22 
* @version 1.0 
*/ 
public class HeapSort implements SortUtil.Sort{  
   
    /* (non-Javadoc) 
     * @see org.rut.util.algorithm.SortUtil.Sort#sort(int[]) 
     */ 
    public void sort(int[] data) {  
        MaxHeap h=new MaxHeap();  
        h.init(data);  
        for(int i=0;i<data.length;i++)  
            h.remove();  
        System.arraycopy(h.queue,1,data,0,data.length);  
    }  
   
   
     private static class MaxHeap{  
           
          
        void init(int[] data){  
            this.queue=new int[data.length+1];  
            for(int i=0;i<data.length;i++){  
                queue[++size]=data[i];  
                fixUp(size);  
            }  
        }  
           
        private int size=0;  
   
        private int[] queue;  
                  
        public int get() {  
            return queue[1];  
        }  
   
        public void remove() {  
            SortUtil.swap(queue,1,size--);  
            fixDown(1);  
        }  
        //fixdown  
        private void fixDown(int k) {  
            int j;  
            while ((j = k ><< 1) <= size) {  
                if (j < size && queue[j]<queue[j+1])  
                    j++;   
                if (queue[k]>queue[j]) //不用交换  
                    break;  
                SortUtil.swap(queue,j,k);  
                k = j;  
            }  
        }  
        private void fixUp(int k) {  
            while (k > 1) {  
                int j = k >> 1;  
                if (queue[j]>queue[k])  
                    break;  
                SortUtil.swap(queue,j,k);  
                k = j;  
            }  
        }  
   
    }  
   
}  
   
   
SortUtil:  
   
package org.rut.util.algorithm;  
   
import org.rut.util.algorithm.support.BubbleSort;  
import org.rut.util.algorithm.support.HeapSort;  
import org.rut.util.algorithm.support.ImprovedMergeSort;  
import org.rut.util.algorithm.support.ImprovedQuickSort;  
import org.rut.util.algorithm.support.InsertSort;  
import org.rut.util.algorithm.support.MergeSort;  
import org.rut.util.algorithm.support.QuickSort;  
import org.rut.util.algorithm.support.SelectionSort;  
import org.rut.util.algorithm.support.ShellSort;  
   
/** 
* @author treeroot 
* @since 2010-11-22 
* @version 1.0 
*/ 
public class SortUtil {  
    public final static int INSERT = 1;  
   
    public final static int BUBBLE = 2;  
   
    public final static int SELECTION = 3;  
   
    public final static int SHELL = 4;  
   
    public final static int QUICK = 5;  
   
    public final static int IMPROVED_QUICK = 6;  
   
    public final static int MERGE = 7;  
   
    public final static int IMPROVED_MERGE = 8;  
   
    public final static int HEAP = 9;  
   
    public static void sort(int[] data) {  
        sort(data, IMPROVED_QUICK);  
    }  
    private static String[] name={  
            "insert","bubble","selection","shell","quick","improved_quick","merge","improved_merge","heap" 
    };  
      
    private static Sort[] impl=new Sort[]{  
            new InsertSort(),  
            new BubbleSort(),  
            new SelectionSort(),  
            new ShellSort(),  
            new QuickSort(),  
            new ImprovedQuickSort(),  
            new MergeSort(),  
            new ImprovedMergeSort(),  
            new HeapSort()  
    };  
   
    public static String toString(int algorithm){  
        return name[algorithm-1];  
    }  
      
    public static void sort(int[] data, int algorithm) {  
        impl[algorithm-1].sort(data);  
    }  
   
    public static interface Sort {  
        public void sort(int[] data);  
    }  
   
    public static void swap(int[] data, int i, int j) {  
        int temp = data[i];  
        data[i] = data[j];  
        data[j] = temp;  
    }  
}