102 lines
4.2 KiB
Markdown
102 lines
4.2 KiB
Markdown
# Food Chain
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Write a program that generates the lyrics of the song 'I Know an Old Lady Who Swallowed a Fly'
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Write a program that generates the lyrics to the song
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"I know an old lady who swallowed a fly". While you could
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copy/paste the lyrics, or read them from a file, this
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problem is much more interesting if you approach it
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algorithmically.
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This is a [cumulative song](http://en.wikipedia.org/wiki/Cumulative_song) of unknown origin.
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This is one of many common variants.
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```plain
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I know an old lady who swallowed a fly.
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I don't know why she swallowed the fly. Perhaps she'll die.
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I know an old lady who swallowed a spider.
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It wriggled and jiggled and tickled inside her.
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She swallowed the spider to catch the fly.
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I don't know why she swallowed the fly. Perhaps she'll die.
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I know an old lady who swallowed a bird.
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How absurd to swallow a bird!
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She swallowed the bird to catch the spider that wriggled and jiggled and tickled inside her.
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She swallowed the spider to catch the fly.
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I don't know why she swallowed the fly. Perhaps she'll die.
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I know an old lady who swallowed a cat.
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Imagine that, to swallow a cat!
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She swallowed the cat to catch the bird.
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She swallowed the bird to catch the spider that wriggled and jiggled and tickled inside her.
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She swallowed the spider to catch the fly.
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I don't know why she swallowed the fly. Perhaps she'll die.
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I know an old lady who swallowed a dog.
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What a hog, to swallow a dog!
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She swallowed the dog to catch the cat.
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She swallowed the cat to catch the bird.
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She swallowed the bird to catch the spider that wriggled and jiggled and tickled inside her.
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She swallowed the spider to catch the fly.
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I don't know why she swallowed the fly. Perhaps she'll die.
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I know an old lady who swallowed a goat.
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Just opened her throat and swallowed a goat!
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She swallowed the goat to catch the dog.
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She swallowed the dog to catch the cat.
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She swallowed the cat to catch the bird.
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She swallowed the bird to catch the spider that wriggled and jiggled and tickled inside her.
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She swallowed the spider to catch the fly.
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I don't know why she swallowed the fly. Perhaps she'll die.
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I know an old lady who swallowed a cow.
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I don't know how she swallowed a cow!
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She swallowed the cow to catch the goat.
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She swallowed the goat to catch the dog.
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She swallowed the dog to catch the cat.
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She swallowed the cat to catch the bird.
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She swallowed the bird to catch the spider that wriggled and jiggled and tickled inside her.
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She swallowed the spider to catch the fly.
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I don't know why she swallowed the fly. Perhaps she'll die.
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I know an old lady who swallowed a horse.
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She's dead, of course!
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```
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## Getting Started
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Make sure you have read the [getting started with C++](http://help.exercism.io/getting-started-with-cpp.html)
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page on the [exercism help site](http://help.exercism.io/). This covers
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the basic information on setting up the development environment expected
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by the exercises.
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## Passing the Tests
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Get the first test compiling, linking and passing by following the [three
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rules of test-driven development](http://butunclebob.com/ArticleS.UncleBob.TheThreeRulesOfTdd).
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Create just enough structure by declaring namespaces, functions, classes,
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etc., to satisfy any compiler errors and get the test to fail. Then write
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just enough code to get the test to pass. Once you've done that,
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uncomment the next test by moving the following line past the next test.
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```C++
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#if defined(EXERCISM_RUN_ALL_TESTS)
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```
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This may result in compile errors as new constructs may be invoked that
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you haven't yet declared or defined. Again, fix the compile errors minimally
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to get a failing test, then change the code minimally to pass the test,
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refactor your implementation for readability and expressiveness and then
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go on to the next test.
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Try to use standard C++11 facilities in preference to writing your own
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low-level algorithms or facilities by hand. [CppReference](http://en.cppreference.com/)
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is a wiki reference to the C++ language and standard library. If you
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are new to C++, but have programmed in C, beware of
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[C traps and pitfalls](http://www.slideshare.net/LegalizeAdulthood/c-traps-and-pitfalls-for-c-programmers).
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## Source
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Wikipedia [view source](http://en.wikipedia.org/wiki/There_Was_an_Old_Lady_Who_Swallowed_a_Fly)
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