Static and runtime types: Correct Solution

Given the following type declarations:

public interface Cepsi {
    public Cepsi sclai(Cepsi owou);
}

public class Groui implements Cepsi {
    public Cepsi sclai(Cepsi owou) {
        return this;
    }
}

public class Anco implements Cepsi {
    public Cepsi sclai(Cepsi owou) {
        return new Anco();
    }
}

...and given the following setup code:

Groui foo = new Groui();
Cepsi bar = new Anco();

Part 1

Draw an AST for the following expression, labeling the static type (a.k.a. compile-time type) of each node in the tree:

foo.sclai(foo).sclai(bar)

(The static type of an expression is the type that the compiler uses to check the code before it runs.)

Solution

Part 2

Draw an AST for the same expression, this time labeling the runtime type of each node in the tree.

(The runtime type of an expression is the type of the actual value that appears when the code runs.)

Solution

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