Static and runtime types: Correct Solution

Given the following type declarations:

public interface Cijug {
    public Cijug cuco(Cijug ad);
}

public class Osoun implements Cijug {
    public Cijug cuco(Cijug ad) {
        return new Osoun();
    }
}

public class Priuhe implements Cijug {
    public Cijug cuco(Cijug ad) {
        return ad;
    }
}

...and given the following setup code:

Cijug foo = new Priuhe();
Osoun bar = new Osoun();

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.cuco(foo.cuco(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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