Algs4-2.1.37部分有序

2.1.37部分有序。编写一个测试用例，生成部分有序的数组，包括：
1)95%有序，其余部分为随机值;
2)所有元素和它们的正确位置的距离都不超过10;
3)5%的元素随机分布在整个数组中，剩下的数据都是有序的。
评估并验证这些输入数据对本节讨论的算法的性能的影响。
插入排序在左边有序，右边随机的情况下排序性能最差，其他情况下性能较好。
选择排序在所有情况下性能都较差。
希尔排序对所有情况性能都比较好，在左边95%有序时性能略差。

import java.util.Arrays;
public class E2d1d37
{
    public static double time (String alg,Double[] a)
    {
        Stopwatch timer =new Stopwatch();
        if(alg.equals("Insertion")) Insertion.sort(a);
        if(alg.equals("Selection")) Selection.sort(a);
        if(alg.equals("Shell")) Shell.sort(a);
      // if(alg.equals("Merge")) Merge.sort(a);
      // if(alg.equals("Quick")) Quick.sort(a);
      // if(alg.equals("Heap")) Heap.sort(a);
        return timer.elapsedTime();
    }

    public static double timeRandomInput(String alg,int N,int T,int probabilityTYPE)
    {
        double total =0.0;
        Double[] a=new Double[N];

        if (probabilityTYPE==0)
        {
            for (int t=0;t<T;t++)
            {
                LeftRandom95sorted(a);
                total+=time(alg,a);
            }
        }
        //probabilityTYPE=1 Poisson distribution
        if (probabilityTYPE==1)
        {
            for (int t=0;t<T;t++)
            {
                RightRandom95sorted(a);
                total+=time(alg,a);
            }
        }
        //probabilityTYPE=2 Geometric distribution
        if (probabilityTYPE==2)
        {
            for (int t=0;t<T;t++)
            {
                uniform5Random95sorted(a);
                total+=time(alg,a);
            }
        }
         //probabilityTYPE=3 Geometric distribution
        if (probabilityTYPE==3)
        {
            for (int t=0;t<T;t++)
            {
                distance10(a);
                total+=time(alg,a);
            }
        }
       return total;
    }//end timeRandomInput

    public static void LeftRandom95sorted(Double[] a)
    {
        for (int i=0;i<a.length;i++)
             a[i]=StdRandom.uniform();
        Arrays.sort(a);
        int rate5=(int)0.05*a.length;
        for(int i=0;i<rate5;i++)
             a[i]=StdRandom.uniform();
    }

      public static void RightRandom95sorted(Double[] a)
    {

        for (int i=0;i<a.length;i++)
             a[i]=StdRandom.uniform();
        Arrays.sort(a);
        int rate95=(int)0.95*a.length;
        for(int i=rate95;i<a.length;i++)
             a[i]=StdRandom.uniform();
    }

     public static void uniform5Random95sorted(Double[] a)
    {
        for (int i=0;i<a.length;i++)
             a[i]=StdRandom.uniform();
        Arrays.sort(a);
        int rate5=(int)0.05*a.length;
        for(int i=0;i<rate5;i++);
             a[StdRandom.uniform(0,a.length)]=StdRandom.uniform();
    }

    public static void distance10(Double[] a)
    {
        for (int i=0;i<a.length;i++)
             a[i]=StdRandom.uniform();
        Arrays.sort(a);
        int distance=10;
        int postion;
        Double temp;
        for(int i=0;i<a.length-distance;i++)
        {
            postion=StdRandom.uniform(i+1,i+distance+1);
            temp=a[i];
            a[i]=a[postion];
            a[postion]=temp;
        }

        for(int i=a.length-1;i>=a.length-distance;i--)
        {
            postion=StdRandom.uniform(i-distance,a.length);
            temp=a[i];
            a[i]=a[postion];
            a[postion]=temp;
        }
    }

    public static void main(String[] args)
    {

        Integer N=Integer.parseInt(args[0]);
        Integer T=Integer.parseInt(args[1]);

        String[] CASEmem=new String[4];
        CASEmem[0]="LeftRandom95sorted";
        CASEmem[1]="95sortedRightRandom";
        CASEmem[2]="uniform5Random95sorted";
        CASEmem[3]="distance10";


         Double time;
         StdOut.printf("---Insertion---\n");
          time=timeRandomInput("Insertion",N,T,0);
         StdOut.printf("For %d double with case %25s,spend time=%.2f\n",N,CASEmem[0],time);
         time =timeRandomInput("Insertion",N,T,1);
         StdOut.printf("For %d double with case %25s,spend time=%.2f\n",N,CASEmem[1],time);
         time =timeRandomInput("Insertion",N,T,2);
         StdOut.printf("For %d double with case %25s,spend time=%.2f\n",N,CASEmem[2],time);
         time =timeRandomInput("Insertion",N,T,3);
         StdOut.printf("For %d double with case %25s,spend time=%.2f\n",N,CASEmem[3],time);


         StdOut.printf("---Selection---\n");
         time =timeRandomInput("Selection",N,T,0);
         StdOut.printf("For %d double with case %25s,spend time=%.2f\n",N,CASEmem[0],time);
         time =timeRandomInput("Selection",N,T,1);
         StdOut.printf("For %d double with case %25s,spend time=%.2f\n",N,CASEmem[1],time);
         time =timeRandomInput("Selection",N,T,2);
         StdOut.printf("For %d double with case %25s,spend time=%.2f\n",N,CASEmem[2],time);
         time =timeRandomInput("Selection",N,T,3);
         StdOut.printf("For %d double with case %25s,spend time=%.2f\n",N,CASEmem[3],time);

         StdOut.printf("---Shell---\n");
         time =timeRandomInput("Shell",N,T,0);
         StdOut.printf("For %d double with case %25s,spend time=%.2f\n",N,CASEmem[0],time);
         time =timeRandomInput("Shell",N,T,1);
         StdOut.printf("For %d double with case %25s,spend time=%.2f\n",N,CASEmem[1],time);
         time =timeRandomInput("Shell",N,T,2);
         StdOut.printf("For %d double with case %25s,spend time=%.2f\n",N,CASEmem[2],time);
         time =timeRandomInput("Shell",N,T,3);
         StdOut.printf("For %d double with case %25s,spend time=%.2f\n",N,CASEmem[2],time);

    }
}

Algs4-2.1.37部分有序

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