Puzzle 1
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Four children play ball until one smashes a nearby window.

Anna cries: "It was Boris."
Boris replies: "No, it was Christa."
Christa adds: "Boris lies!"
Detlef says: "It wasn't me."

Exactly one of the children speaks the truth.



Puzzle 2
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Transsilvania is inhabited not only by truthful humans but also by
vampires who always lie.  Not everybody knows that every second
Transsilvanian, be it human or vampire, is insane.  These insanes
believe true things to be wrong and false things correct.

For example, all sane humans know that the earth is round.  The
insane humans in contrast believe it is flat.  Sane vampires know
about the globe but deny it is a sphere.  And the insane vampires,
finally, believe that the earth is a disc but claim the opposite.

On a journey through the Balkans in a suspicious area, Inspector
Craig meet the girls Minna and Lucy.  He has been warned that one of
the two belonged to the family of Dracula; which of the two he was
unable to tell.

Since after dusk Craig didn't want to get in trouble with vampires,
he asked them: "Please tell me something about you!"

Lucy: "We are both insane."

Craig: "Is that true?"

Minna: "Of course not!"

With whom of the two did the inspector spend the evening?