
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
Suppose that each of \( n \) people knows exactly one piece of information, and all \( n \) pieces are different. Every time person \( A \) phones person \( B \), \( A \) tells \( B \) everything he knows, while \( B \) tells \( A \) nothing. What is the minimum number of phone calls between pairs of people needed for everyone to know everything?

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