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17 lines
548 B
17 lines
548 B
3 years ago
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Exercise 3.22: Instead of representing a queue
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as a pair of pointers, we can build a queue as a procedure with local state.
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The local state will consist of pointers to the beginning and the end of an
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ordinary list. Thus, the make-queue procedure will have the form
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(define (make-queue)
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(let ((front-ptr … )
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(rear-ptr … ))
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⟨definitions of internal procedures⟩
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(define (dispatch m) …)
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dispatch))
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Complete the definition of make-queue and provide implementations of the
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queue operations using this representation.
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