Java program to find Factorial of a number using while loop.

public class Factorial {
    public static void main(String[] args) {
        int num = 5, i = 1;
        long factorial = 1;
        while(i <= num)
        {
            factorial *= i;
            i++;
        }
        System.out.printf("Factorial of %d = %d", num, factorial);
    }
}