
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
A and B start moving towards each other from points A and B, respectively, at the same time with constant speeds. They first meet at a point 700m away from point A. Then, they continue moving, and after reaching points B and A respectively, they immediately return. They meet for the second time at a point 400m away from point B. What is the distance between points A and B in meters?

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