实验代码：

import java.util.Scanner;

class chazhao {



    public static void main(String[] args) {
        Scanner sc=new Scanner(System.in);
        System.out.println("请输入你要的数组");
        String line= sc.nextLine();
        String[] lineArr=line.split(" ");
        int[] list=new int[lineArr.length];
        for (int i = 0; i < list.length ; i++) {
            list[i]=Integer.parseInt(lineArr[i]);

        }
        for (int i = 0; i < list.length-3 ; i++) {
            if(list[i]==list[i+1]&&list[i+1]==list[i+2]&&list[i+2]==list[i+3]){
                System.out.println("true");
                break;
            }
            else {
                System.out.println("false");

            }
        }

    }




}

运行结果如图所示：

第二题代码：

import java.util.Arrays;
import java.util.Scanner;

 class Code_31 {
     public static void main(String[] args) {
          Scanner input=new Scanner(System.in);

          System.out.print("Enter list1 size and contents:");
          int length1=input.nextInt();
          int[] list1=new int[length1];
          for(int i=0;i<list1.length;i++){
               list1[i]=input.nextInt();
          }

          System.out.print("Enter list2 size and contents:");
          int length2=input.nextInt();
          int[] list2=new int[length2];
          for(int i=0;i<list2.length;i++){
               list2[i]=input.nextInt();
          }

          for(int i=0;i<merge(list1,list2).length;i++)
               System.out.print(merge(list1,list2)[i]+" ");
     }

     public static int[] merge(int[] list1,int[] list2){
          int[] list3=new int[list1.length+list2.length];
          for(int i=0;i<list1.length;i++){
               list3[i]=list1[i];
          }
          for(int i=list1.length,j=0;i<list1.length+list2.length;i++,j++){
               if(j>list2.length)
                    break;
               list3[i]=list2[j];
          }
          Arrays.sort(list3);
          return list3;
     }
}

运行结果: