17 lines
234 B
OCaml
17 lines
234 B
OCaml
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structure Queue:> QUEUE =
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struct
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type 'a queue = 'a list
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val empty_queue = nil
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exception Empty
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fun enq q x = q @ [x]
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fun deq nil = raise Empty
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| deq (x::q) = (x, q)
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fun empty nil = true
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| empty _ = false
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end;
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