# Misunderstanding about a problem in algorithms

Consider the following sequence
$$mathcal{S}=langle3,1,4,1,5,9,2,6,5,3,8,9,7,9,3,2,3,8,4,6,2,7,9rangle$$ We can imagine
some adjacent elements of $$mathcal{S}$$ as a number. For example,
$$5$$, and 3 and $$8$$ form the number $$538$$. We say two number in above
format is disjoint, if there is nothing common element between them.
With respect to $$mathcal{S}$$, what is the maximum number of disjoint
numbers we can make such that have increasing order from left to right?

I think if we consider only numbers with $$1$$ digit, then we have at most nine numbers that have no common element and sorted in increasing order from left to right. But the answer is $$10$$ numbers. Maybe i have a misunderstanding about the problem, so any one have a idea to clarify me that why answer become $$10$$?