
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
Let $[x]$ denote the greatest integer less than or equal to $x$. For example, $[1.7]=1$, $[-1.7]=-2$. Based on this definition, perform the following operations:  
(1) $[2.3]-[6.3]$  
(2) $[4]-[-2.5]$  
(3) $[-3.8]\times[6.1]$  
(4) $[0]\times[-4.5]$．

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