public class Primer
{
    public static boolean isDivisibleBy(int n, int i)
    {
        if ((n % i) == 0)
            return true;
        else
            return false;
    }
    
    public static boolean isPrime(int number)
    {
        if (number == 1)
            return true;
        else if (number == 2)
            return true;
        else if (isDivisibleBy(number, 2))
        {
            return false;
        }
        else
        {
            int i = 3;
            while (!isDivisibleBy(number, i))
            {
                i+=2;    
            }
            if (i == number)
                return true;
            else
                return false;
        }
    }
    
    public static void main(String args[])
    {
        System.out.print("Enter number: ");
        int number = Console.readInt();
     
        int sum = 0;
        for (int i = 0; i < number; i++)
        {
            if (isPrime(i))
               sum += i;
        }
        System.out.println("sum is " + sum);
    }
}