68 lines
2.1 KiB
Markdown
68 lines
2.1 KiB
Markdown
# Saddle Points
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Detect saddle points in a matrix.
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So say you have a matrix like so:
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```text
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1 2 3
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|---------
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1 | 9 8 7
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2 | 5 3 2 <--- saddle point at column 1, row 2, with value 5
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3 | 6 6 7
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```
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It has a saddle point at column 1, row 2.
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It's called a "saddle point" because it is greater than or equal to
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every element in its row and less than or equal to every element in
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its column.
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A matrix may have zero or more saddle points.
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Your code should be able to provide the (possibly empty) list of all the
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saddle points for any given matrix.
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The matrix can have a different number of rows and columns (Non square).
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Note that you may find other definitions of matrix saddle points online,
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but the tests for this exercise follow the above unambiguous definition.
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## Getting Started
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Make sure you have read the "Guides" section of the
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[C track][c-track] on the Exercism site. 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][3-tdd-rules].
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The included makefile can be used to create and run the tests using the `test`
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task.
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make test
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Create just the functions you need to satisfy any compiler errors and get the
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test to fail. Then write just enough code to get the test to pass. Once you've
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done that, move onto the next test.
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As you progress through the tests, take the time to refactor your
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implementation for readability and expressiveness and then go on to the next
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test.
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Try to use standard C99 facilities in preference to writing your own
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low-level algorithms or facilities by hand.
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## Source
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J Dalbey's Programming Practice problems [http://users.csc.calpoly.edu/~jdalbey/103/Projects/ProgrammingPractice.html](http://users.csc.calpoly.edu/~jdalbey/103/Projects/ProgrammingPractice.html)
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## Submitting Incomplete Solutions
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It's possible to submit an incomplete solution so you can see how others have completed the exercise.
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[c-track]: https://exercism.io/my/tracks/c
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[3-tdd-rules]: http://butunclebob.com/ArticleS.UncleBob.TheThreeRulesOfTdd
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