
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
Form a four-digit number using the digits 1, 2, and 3, with the rule that all three digits must be used, but the same digit cannot be adjacent. Calculate the total number of such four-digit numbers.

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