triangle.rb

# Triangle Project Code.

# Triangle analyzes the lengths of the sides of a triangle
# (represented by a, b and c) and returns the type of triangle.
#
# It returns:
#   :equilateral  if all sides are equal
#   :isosceles    if exactly 2 sides are equal
#   :scalene      if no sides are equal
#
# The tests for this method can be found in
#   about_triangle_project.rb
# and
#   about_triangle_project_2.rb
#
def triangle(a, b, c)
  if [a,b,c].min<=0
  	raise TriangleError
  elsif a==b && b==c
  	return :equilateral
  elsif a!=b && b!=c && c!=a
  	return :scalene
  else
  	a,b,c=[a,b,c].sort
  	unless a+b<=c
  		return :isosceles
  	else
  		raise TriangleError
  	end
  end
end

# Error class used in part 2.  No need to change this code.
class TriangleError < StandardError
end