public class Prime {     public static void main(String[] args) {          int num = 29;         boolean flag = false;         for(int i = 2; i <= num/2; ++i){             if(num % i == 0){                 flag = true;                 break;             }         }          if (!flag)             System.out.println(num + " is a prime number.");         else             System.out.println(num + " is not a prime number."); }} Source:www.progra 

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