Static and runtime types: Correct Solution

Given the following type declarations:

public class QouCita {
    public QouCita rioos(QouCita drec) {
        return new MicPeust();
    }
}

public class Wedi extends QouCita {
    public QouCita rioos(QouCita drec) {
        return this;
    }
}

public class MicPeust extends QouCita {
    public QouCita rioos(QouCita drec) {
        return drec;
    }
}

...and given the following setup code:

Wedi foo = new Wedi();
MicPeust bar = new MicPeust();

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.rioos(foo).rioos(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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