多线程素数判定程序：键盘输入与并发计算

import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;

public class Primejudge implements Runnable {

    static List<Integer> list = new ArrayList<Integer>();
    static List<String> list1 = new ArrayList<String>();

    public static void main(String args[]) {
        Primejudge primejudge = new Primejudge();
        Thread thread1 = new Thread(primejudge);
        Thread thread2 = new Thread(primejudge);
        Thread thread3 = new Thread(primejudge);
        Thread thread4 = new Thread(primejudge);
        Thread thread5 = new Thread(primejudge);
        Thread thread6 = new Thread(primejudge);
        Thread thread7 = new Thread(primejudge);
        Thread thread8 = new Thread(primejudge);
        Thread thread9 = new Thread(primejudge);
        Thread thread10 = new Thread(primejudge);
        Scanner sc = new Scanner(System.in); 
      System.out.println("请输入你要判断的数字个数:");        
                int n = sc.nextInt();
                for (int i = 0; i < n; i++) {
                    System.out.println("请输入第" + (i + 1) + "个数");
                    int k = sc.nextInt();
                    list.add(k);