1 package ltb20180106; 2 3 public class FindPrime implements Runnable{ 4 5 private int prime; 6 private int q; 7 private int w; 8 9 public FindPrime(int nn,int mm) { 10 11 q=nn; 12 w=mm; 13 } 14 15 public void run() { 16 17 getFindPrime(q,w); 18 19 } 20 21 public synchronized void getFindPrime(int min,int max) { 22 23 int k=max; 24 int j=min; 25 26 if(max<min) { 27 28 System.out.println("最大值不能小于最小值,请重新输入!"); 29 30 }else if(max<=0||min<0) { 31 32 System.out.println("输入值不能是负数,或者最大值不能是零."); 33 } 34 35 for(int i=k;i>j;i--) { 36 37 if(i==1) { //1不是素数 38 39 continue; 40 } 41 42 prime=i%2;//去掉偶数 43 44 if(prime==0&&i>3) { 45 46 continue; 47 } 48 49 prime=i%3;//去掉整除3的数,但是要大于7 50 51 if(prime==0&&i>7) { 52 53 continue; 54 55 } 56 57 prime=i%5;//去掉整除5的数,但是要大于7 58 59 60 if(prime==0&&i>7) { 61 62 continue; 63 64 } 65 66 prime=i%7;//去掉整除7的数,,但是要大于7 67 68 69 if(prime==0&&i>7) { 70 71 continue; 72 73 } 74 75 76 System.out.println("["+Thread.currentThread().getName()+"]"+"素数:"+i+"["+prime+"]"); 77 78 79 } 80 81 } 82 83 public static void main(String[] args) { 84 85 Thread t1=new Thread(new FindPrime(0,1000)); 86 t1.start(); 87 Thread t2=new Thread(new FindPrime(1001,2000)); 88 t2.start(); 89 Thread t3=new Thread(new FindPrime(2001,3000)); 90 t3.start(); 91 92 } 93 94 }
