随机数生成数组 截取这其中一部分遍历

package test;
    import java.util.Scanner;
    import java.util.Random;
public class test01 {
    public static void main(String[] args){
        Scanner in = new Scanner(System.in);
        System.out.println("请输入你要遍历的数组from：");
        int from = in.nextInt();
        System.out.println("to：  ");
        int to = in.nextInt();

        int[] arr = new int[100];
        Random r = new Random();
        for(int i = 0; i<arr.length; i++)
        {
            arr[i] = r.nextInt(100);
        }
        int[] copy = copypofrange(arr, from, to);

        System.out.println("遍历后的数组是：");
        System.out.print("[");
        for(int s = 0; s<copy.length; s++)
        {
            if(s<copy.length - 1)
            System.out.print(copy[s] + ", ");
            else if(s == copy.length - 1)
                System.out.print(copy[s]);
        }
        System.out.println("]");
    }


    public static int[] copypofrange(int[] arr,int from,int to ) {
        int sum = 0;
        int[] newarr = new int[to - from];
        for(int i = from; i<to; i++)
        {
            newarr[sum] = arr[i];
            sum++;
        }
        return newarr;





    }





}