Static and runtime types: Correct Solution

Given the following type declarations:

public interface Skatig {
    public Skatig thedi(Skatig ac);
}

public class Sqisemn implements Skatig {
    public Skatig thedi(Skatig ac) {
        return this;
    }
}

public class Pesan implements Skatig {
    public Skatig thedi(Skatig ac) {
        return ac;
    }
}

...and given the following setup code:

Pesan foo = new Pesan();
Sqisemn bar = new Sqisemn();

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.thedi(bar).thedi(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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