8. (10 points) In the expression $1 \square 2 \square 3 \square 6 \square 12$, fill in the $\square$ with “ + ” or “ - ”. The total number of different natural number results that can be obtained is $\qquad$.
【Solution】Solution: According to the problem, we have:
all are “ $+$ ”, 1 way,
contains 1 “ - ”, “ - ” can be placed in any of the 4 positions, a total of 4 ways.
contains 2 “ - ”, “ - ” cannot be placed before 12, choosing 2 out of the other three positions gives 3 ways, contains 3 “ - ”, “ - ” cannot be placed before 12, only 1 way.

In total, there are 9 ways.
Therefore, the answer is: 9.