79 lines
2.9 KiB
Markdown
79 lines
2.9 KiB
Markdown
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# Purpose
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Prove I'm not an idiot.
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As an exercise, I decided to do this homework in C++. As I haven't
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written any C++ in 15 years, this was... entertaining.
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# Task #1
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Write a function which computes the some [sic] of q, q^2, q^3, … q^n,
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where "^" denotes power or exponent. For example, the sum of
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2,4,8,16 is 30. What is the complexity?
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The complexity is linear. This is a basic sigma function, once you know
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the underlying formula, production is simple. The requirements for the
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code (that you determine both the base of your exponent collection, and
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know how many you want) are difficult to discern from a simple reading
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of the instructions.
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If I'd allowed myself to use boost(), I've written this using the
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accumulate() function, but I'd have to figure out how to create a range
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iterator.
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# Task #2
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Write a function GetMax(Node list), which finds the maximum integer
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value in the list
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In order to make this at all interesting, I set myself the task of
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learning how to create function templates, which we didn't have back in
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1999. It turned out to be relatively straightforward, although the
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"typename" declarator in the template before std::list<t>::iterator is a
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bit of cargo-cult I got from compiler's warnings; I really need to go
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back and read some of Alexandrescu's books, especially since I got them
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all for free after spotting a typo in one back in 1997 or so.
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I've provided a Makefile and unit tests using the Aeryn C++ Test
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Framework. It was a framework chosen at random from a list I found
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after searching for "C++ Test Frameworks," I can't comment on its
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quality, but it did the job. It looked familiar enough compared to
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JUnit or Mocha.
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# Commentary
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It's been a long time since I wrote C++. The syntactical noise of C++
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annoys me a bit since I've started writing in "An elegant language for a
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more civilized time," and I'm so far out of experience with it that the
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modern paradigm of Resource Allocation Is Initialization and all of the
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wonderful new toys like auto, unique_ptr, lambdas and the like would
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take me a month or two to catch up.
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If I'd written this in Javascript they'd have been one-liners:
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exponentialSum = (base, count) =>
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_.reduce(_.range(1, count + 1), ((m, v) => return m + Math.pow(base, v)), 0);
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largestValue = _.max;
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or:
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largestValue = (list) => Math.max.apply(Math, list);
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I'm pretty sure that the functions I wrote have simple equivalents in
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some library somewhere. Boost seems to have just about everything.
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The Makefile is just something I pulled out of an old project and
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cleaned up for the purposes of this exercise.
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Total time spent: Approximately 75 minutes.
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# Addenda
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The [sic] in the original task description is a bit of a snark. That
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and the instruction to "Please use of of [sic] Java/C++/C#/Javascript"
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ought to be professionally embarrassing to someone seeking viable,
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self-respecting candidates.
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