print((function (n)
	for _=1,tonumber(io.stdin:read("*l")) do
		local s = io.stdin:read("*l")
		if s:sub(1,1) == n then n = s:sub(3,3)
		elseif s:sub(3,3) == n then n = s:sub(1,1) end
	end
	return n
end)(io.stdin:read("*l")))