1 package codeTask_FangFa; 2 // 5.30     雙素數就是兩個相差為2的素數。程序顯示所有小于1000的雙素數。按照格式顯示。 3 public class ShuangSuShu { 4     public static void main(String[] args){           //所謂的主方法； 5         int number = 3; 6         int first = 2; 7         System.out. ); 8         while(number<1000){ 9             if(isSuShu(number)){10                 int second = number;11                 if(second-first==2){12                    System.out.println("( "+first+","+second+" )");13                 }14                 first=second;15             }16             number++;17         }18     }19     20     public static boolean isSuShu(int number){                   //判斷下是否是素數；21         for(int divisor=2;divisor<=number/2;divisor++){22             if(number%divisor==0)23             return false;    24         }25         return true;26     }27     28 }