Determine if a triangle is equilateral, isosceles, or scalene.
An equilateral triangle has all three sides the same length.
An isosceles triangle has at least two sides the same length. (It is sometimes specified as having exactly two sides the same length, but for the purposes of this exercise we'll say at least two.)
A scalene triangle has all sides of different lengths.
For a shape to be a triangle at all, all sides have to be of length > 0, and the sum of the lengths of any two sides must be greater than or equal to the length of the third side. See Triangle Inequality.
The case where the sum of the lengths of two sides equals that of the third is known as a degenerate triangle - it has zero area and looks like a single line. Feel free to add your own code/tests to check for degenerate triangles.
-
Go to the root of your PHP exercise directory, which is
<EXERCISM_WORKSPACE>/php. To find the Exercism workspace run% exercism debug | grep Workspace -
Get PHPUnit if you don't have it already.
% wget --no-check-certificate https://phar.phpunit.de/phpunit.phar % chmod +x phpunit.phar -
Execute the tests:
% ./phpunit.phar triangle/triangle_test.php
The Ruby Koans triangle project, parts 1 & 2 http://rubykoans.com
It's possible to submit an incomplete solution so you can see how others have completed the exercise.