
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 sets $A = \{1, 2, 3, 4\}$ and $B = \{-1, -2\}$, let there be a mapping $f: A \rightarrow B$. If every element in set $B$ is an image of elements in $A$ under the mapping $f$, then there are $\boxed{14}$ such mappings.

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