class No203
	def initialize
		@str1 = gets.chomp.to_s.split("")
		@str2 = gets.chomp.to_s.split("")
		@continuity = Array.new
		@count = 0
	end

	def x_or_o(strs)
		strs.each do |str|
			if str == "x"
				@continuity << @count
				@count = 0
			else
				@count += 1
			end
		end
		@continuity << @count
	end

	def run
		self.x_or_o(@str1)
		self.x_or_o(@str2)
		puts @continuity.max
	end
end

no203 = No203.new
no203.run