Not getting what should i do...

I always over think these easy ones

Just declare oublic static String name in each class: public class Solution { public static String name; public static class Cat { public static String name; } public static class Dog { public static String name; }

The requirements say: - In the Solution class, add a public static String variable name. - In the Cat class, add a public static String variable name. - In the Dog class, add a public static String variable name. These are not met. Your confusion seems to be the dot operator as in Solution.name or Dog.name. The dot operator donates hierarchy and is not a literal. Dog.name means "name" in the dog class, same with Solution.name and Cat.name.