各种排序

插入排序:


    package org.rut.util.algorithm.support;
    import org.rut.util.algorithm.SortUtil;
    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;
    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;
    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;
    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;
    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;
    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;
    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;
    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;
    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;
    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;
        }
    }