17 lines
326 B
Common Lisp
17 lines
326 B
Common Lisp
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(defstruct stack
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elements)
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(defun stack-push (element stack)
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(push element (stack-elements stack)))
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(defun stack-pop (stack)(deftype Stack [elements])
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(defun stack-empty (stack)
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(endp (stack-elements stack)))
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(defun stack-top (stack)
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(first (stack-elements stack)))
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(defun stack-peek (stack)
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(stack-top stack))
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