
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
18. Lone Cars. (From 9th grade, 4 points.) On a very long narrow highway, where overtaking is impossible, $n$ cars are driving in random order, each with their preferred speed. If a fast car catches up to a slower one, the fast car has to slow down and drive at the same speed as the slower one. As a result, cars form groups. Find the expected number of "lone" cars, i.e., groups consisting of a single car.

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