
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 sequence $\{a\_n\}$ that satisfies the condition: when $n \geqslant 2$ and $n \in \mathbb{N}^+$, we have $a\_n + a\_{n-1} = (-1)^n \times 3$. Calculate the sum of the first 200 terms of the sequence $\{a\_n\}$.

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