?2.1.32运行时间曲线图。编写一个测试用例,使用StdDraw在各种不同规模的随机输入下将算法的平均运行时间绘制成一张曲线图。可能需要添加一两个命令行参数,请尽量设计一个实用的工具。

1)插入排序

2)选择排序

3)Shell排序

public class E2d1d32{??? 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)??? {??????? double total =0.0;??????? Double[] a=new Double[N];??????? for (int t=0;t<T;t++)??????? {??????????? for (int i=0;i<N;i++)??????????????? a[i]=StdRandom.uniform();??????????? total+=time(alg,a);??????? }??????? return total;??? }//end timeRandomInput??? ??? public static void main(String[] args)??? {??????? String alg=args[0];??????? Integer N=Integer.parseInt(args[1]);??????? Integer T=Integer.parseInt(args[2]);??????? //??????? StdDraw.setXscale(0.0,N*10.0);??????? StdDraw.setYscale(0.0,500);??????? StdDraw.setPenColor(StdDraw.RED);??????? StdDraw.setPenRadius(0.01);??????? //??????? for (int n=10;n<=N;n=1000+n)??????? {????????? //???????? double time=timeRandomInput(alg,n,T);???????? StdDraw.point(n*1.0,time/T);??????? }??????? StdOut.println("The End");??? }}