Program to check whether the number is prime or not in java code example

Example: Program to check whether the number is prime or not in java

public class Main 
{
public static void main(String[] args) 
{
int num = 100;
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");
}
}