
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
Carl computes the number

\[ N = 5^{555} + 6^{666} + 7^{777} \]

and writes it in decimal notation. What is the last digit of \( N \) that Carl writes?

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