
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
For any natural number, define \( ni = 1 \times 2 \times 3 \times \cdots \times n \), such as \( 8i = 1 \times 2 \times 3 \times \cdots \times 8 \); then, find the last digit of the result of the expression \( 2014i + 2013i - 2012i + 2011i + \cdots - 4i + 3i - 2i + 1i \).

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