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42 lines
702 B
42 lines
702 B
2 years ago
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Exercise 1.10: The following procedure computes
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a mathematical function called Ackermann’s function.
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(define (A x y)
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(cond ((= y 0) 0)
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((= x 0) (* 2 y))
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((= y 1) 2)
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(else (A (- x 1)
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(A x (- y 1))))))
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What are the values of the following expressions?
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(A 1 10)
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(A 2 4)
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(A 3 3)
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Consider the following procedures, where A is the procedure
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defined above:
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(define (f n) (A 0 n))
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(define (g n) (A 1 n))
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(define (h n) (A 2 n))
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(define (k n) (* 5 n n))
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Give concise mathematical definitions for the functions computed by the
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procedures f, g, and h for positive integer values of
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n
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. For example, (k n) computes
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5
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n
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2
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.
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