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Message:

there are two ways.

Posted by swapnil on November 15, 2000 at 9:01 AM

hello,
the first way :
...........................................................import java.math.*;
public class test
{
public static void main(String[] args)
{
BigInteger bi=new BigInteger("11098098091");
boolean b=bi.isProbablePrime(1);
System.out.println(b);
}
}
...............................................................

The second way :
Follow the steps and generate the code.
1. let the no. be x
2. take the (positive value) square-root of x and store it in y.
3. y may be a whole no. or a no. with decimals in it.
4. now ceil() this y and store the result in z
5. now test whether the original no. i.e.x is divisible by any one of the no.s from 3 to z (excluding all the even nos. in between).
6. if yes then the no. is NOT prime.
7. if no then the no. is DEFINITELY prime.
..............................................................

hope this solves ur problem
regards,
swapnil