12 lines
331 B
Text
12 lines
331 B
Text
import data.vector
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open nat vector
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definition last {A : Type} : Π {n}, vector A (succ n) → A,
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last (a :: nil) := a,
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last (a :: v) := last v
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theorem last_cons_nil {A : Type} {n : nat} (a : A) : last (a :: nil) = a :=
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rfl
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theorem last_cons {A : Type} {n : nat} (a : A) (v : vector A (succ n)) : last (a :: v) = last v :=
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rfl
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