Count Completed Trips

You are given vehicle event logs in chronological order. Each log contains a license plate and one of three event types: entry, road, or exit. A completed trip is counted when the same plate appears in order as entry -> road -> exit. Count the total number of completed trips across all plates. Function Description Complete the function countCompletedTrips in the editor below. countCompletedTrips has the following parameter:

• String[] logs: log lines formatted as "plate event" Returns int: the number of completed trips.

Constraints

• Logs are processed in chronological order.
• The same plate may complete multiple trips.
• Incomplete or invalid event sequences should not be counted.

Example 1

Input:

logs = ["A entry", "A road", "A exit"]

Output:

1

Explanation: Plate A completes one valid entry -> road -> exit sequence.

Example 2

Input:

logs = ["A entry", "B entry", "A road", "A exit", "B exit"]

Output:

1

Explanation: Plate A completes one trip. Plate B does not, because it never reaches the road event before exiting.