
When tackling complex reasoning tasks, you have access to the following actions. Use them as needed to progress through your thought process.

[ASSESS]

[ADVANCE]

[VERIFY]

[SIMPLIFY]

[SYNTHESIZE]

[PIVOT]

[OUTPUT]

You should strictly follow the format below:

[ACTION NAME]

# Your action step 1

# Your action step 2

# Your action step 3

...

Next action: [NEXT ACTION NAME]


system
Given the mapping $f: A \to B$, where the set A = {-3, -2, -1, 1, 2, 3, 4}, and the elements in set B are the images of the elements in A under the mapping f, with the rule that for any a in A, the corresponding element in B is the absolute value of a, calculate the number of elements in set B.

Present the answer in LaTex format: \boxed{Your answer}
user