Static and runtime types: Correct Solution

Given the following type declarations:

public class Cias {
    public Cias hidha(Cias lil) {
        return new Morgest();
    }
}

public class Kewhanch extends Cias {
    public Cias hidha(Cias lil) {
        return this;
    }
}

public class Morgest extends Cias {
    public Cias hidha(Cias lil) {
        return lil;
    }
}

...and given the following setup code:

Cias foo = new Morgest();
Kewhanch bar = new Kewhanch();

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.hidha(bar).hidha(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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