length of longest consecutive sequence in array of integers

longest_consecutive_sequence.rb

def longest_consecutive_sequence(a)
  ans = 0

  a.length.times do |i|
    unless a.include?(a[i] - 1)
      j = a[i]

      while(a.include?(j)) do
        j += 1
      end

      ans = j - a[i] if (ans < j - a[i])
    end
  end

  return ans
end

puts longest_consecutive_sequence([36, 41, 56, 35, 44, 33, 34, 92, 43, 32, 42]) ## returns 5 i.e. [32, 33, 34, 35, 36]
puts longest_consecutive_sequence([1, 9, 3, 10, 4, 20, 2]) ## returns 4 i.e. [1, 2, 3, 4]