Distance Between Bus Stops

Let’s break down the solution into simpler steps.

We have two possible paths to go from the start to the destination:

  1. Moving clockwise from start to destination.
  2. Moving counterclockwise from start to destination.

We’ll calculate the distance for both paths and return the minimum distance.

Here’s the code:

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class Solution:
    def distanceBetweenBusStops(self, distance: List[int], start: int, destination: int) -> int:
        # If start is greater than destination, swap them to make sure we move forward in the list
        if start > destination:
            start, destination = destination, start

        # Calculate the clockwise distance from start to destination
        clockwise_distance = 0
        for i in range(start, destination):
            clockwise_distance += distance[i]

        # Calculate the total distance in the circle
        total_distance = sum(distance)

        # Calculate the counterclockwise distance using total distance minus clockwise distance
        counterclockwise_distance = total_distance - clockwise_distance

        # Return the minimum of both distances
        return min(clockwise_distance, counterclockwise_distance)

In the code, we first make sure that start is less than destination by swapping them if needed. Then, we calculate the distance in both directions and return the minimum.

This implementation is clear and easy to follow, and its time complexity is O(n), where n is the number of bus stops.