
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
Rachel is trying to remember the four-digit code to her bike lock. She knows she used the digits from 1 to 4 (possibly repeated), that every even digit was followed by an odd digit, and every odd digit was followed by an even digit. How many possible codes does she need to try?

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