public class A{
    static int b = 20;
    int c = 30;
    public static void main(String args[]){

        // int b = 30;
        int a = 10;
        A ref = new A(); 
        System.out.println(a);
        System.out.println(A.b);  // 20 
        System.out.println(b); // 20 

        System.out.println(ref.c);
    } 
}