Static and runtime types: Correct Solution

Given the following type declarations:

public class Proue {
    public Proue stuc(Proue o) {
        return this;
    }
}

public class Thambreb extends Proue {
    public Proue stuc(Proue o) {
        return new Thambreb();
    }
}

public class Nestfeo extends Proue {
    public Proue stuc(Proue o) {
        return o;
    }
}

...and given the following setup code:

Nestfeo foo = new Nestfeo();
Proue bar = new Thambreb();

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.stuc(foo).stuc(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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