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)
  # WRITE THIS CODE

  tri, s1, s2 = if c > a || c > b
            [c,a,b]
          elsif b > a || b > c
            [b,a,c]
          else
            [a,b,c]
          end

  if a <= 0 || b <= 0 || c <= 0
    raise TriangleError
  elsif s1 + s2 <= tri
    raise TriangleError
  end

  type = if tri == s1 && tri == s2
        :equilateral
      elsif tri == s1 || tri == s2
        :isosceles
      else
        :scalene
      end

end

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