
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
Use the Euclidean algorithm and the method of continuous subtraction to find the greatest common divisor (GCD) of 840 and 1764, as well as 440 and 556, respectively.

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