22 lines
1.3 KiB
Plaintext
22 lines
1.3 KiB
Plaintext
[[wp:Charles_Babbage|Charles Babbage]], looking ahead to the sorts of problems his Analytical Engine would be able to solve, gave this example:
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{{quote
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| What is the smallest positive integer whose square ends in the digits 269,696?
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| Babbage, letter to Lord Bowden, 1837; see Hollingdale and Tootill, <i>Electronic Computers</i>, second edition, 1970, p. 125.
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}}
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He thought the answer might be 99,736, whose square is 9,947,269,696; but he couldn't be certain.
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;Task
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The task is to find out if Babbage had the right answer — and to do so, as far as your language allows it, in code that Babbage himself would have been able to read and understand.
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As Babbage evidently solved the task with pencil and paper, a similar efficient solution is preferred.
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For these purposes, Charles Babbage may be taken to be an intelligent person, familiar with mathematics and with the idea of a computer; he has written the first drafts of simple computer programmes in tabular form. [[https://collection.sciencemuseum.org.uk/documents/aa110000020 Babbage Archive Series L]].
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;Motivation
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The aim of the task is to write a program that is sufficiently clear and well-documented for such a person to be able to read it and be confident that it does indeed solve the specified problem.
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<br><br>
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