Given an array of numbers, which are perfect squares?

perfect_squares

def get_squares(n)
  n.to_a
  squares = []
  n.each do |i|
    if (i ** 0.5).to_s[-2..-1] == ".0" 
      if squares.include? i
        squares
      else
        squares.push(i) 
      end
    end
  end
  squares.sort  
end