Practical Java language design-generates a random integer between 2-K to determine whether a number is a prime number

1                     import java.io.*; 

2                        import java.util.*;

3                          public class J2_13 { 

4                            public static void main(String a[]) {

5. Construct objects = new objects (system. In);/* construct a struct object. The input parameter is system. In */

6                          System.out.println("Please enter a number to limit the random number that yout want:");

7 int K = bytes. nextint ();/* read an int value K */

8 int P = (INT) (2 + (K-2) * Math. Random ();/* generates a random integer between 2 and K */

9                        if(yes(p)) 

10                     System.out.println(p+" is prime。");  

11                   else 

12                   System.out.println(p+" is not prime。"); 

13                    return; 

14                   } 

15/* determine whether a number is a prime number */

16                   public static boolean yes(int q) { 

17                        boolean t=true; 

18                           for(int i=2;i<q;i++) 

19                               if(q%i==0) { 

20                          t=false; 

21                    break; 

22                    } 

23 return t;/* return a Boolean value */

24                   } 

25       }