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39 lines
928 B
39 lines
928 B
2 years ago
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Exercise 5.14: Measure the number of pushes and
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the maximum stack depth required to compute
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n
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!
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for various small values of
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n
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using the factorial machine shown in Figure 5.11. From your data
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determine formulas in terms of
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n
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for the total number of push operations
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and the maximum stack depth used in computing
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n
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!
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for any
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n
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>
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1
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. Note
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that each of these is a linear function of
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n
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and is thus determined by two
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constants. In order to get the statistics printed, you will have to augment
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the factorial machine with instructions to initialize the stack and print the
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statistics. You may want to also modify the machine so that it repeatedly
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reads a value for
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n
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, computes the factorial, and prints the result (as we
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did for the GCD machine in Figure 5.4), so that you will not
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have to repeatedly invoke get-register-contents,
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set-register-contents!, and start.
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