8. (10 points) In the expression $1 \square 2 \square 3 \square 6 \square 12$, fill in the $\square$ with “+” or “ - ”. A total of 9 different natural number results can be obtained.
【Solution】Solution: According to the problem, we know:
All are “ + ”, 1 way,
Contains 1 “ - ”, the position of “ - ” can be placed in any of the 4 positions, a total of 4 ways.
Contains 2 “ - ”, the position of “ - ” cannot be placed before 12, choosing any 2 out of the other three positions gives 3 ways.
Contains 3 “ - ”, the position of “ - ” cannot be placed before 12, only 1 way.
A total of 9 ways.
Therefore, the answer is: 9.
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 $\qquad$.