1184. Distance Between Bus Stops

Problem

A bus has n stops numbered from 0 to n - 1 that form a circle. We know the distance between all pairs of neighboring stops where distance[i] is the distance between the stops number i and (i + 1) % n.

The bus goes along both directions i.e. clockwise and counterclockwise.

Return the shortest distance between the given start and destination stops.

  Example 1:

Input: distance = [1,2,3,4], start = 0, destination = 1
Output: 1
Explanation: Distance between 0 and 1 is 1 or 9, minimum is 1.

Example 2:

Input: distance = [1,2,3,4], start = 0, destination = 2
Output: 3
Explanation: Distance between 0 and 2 is 3 or 7, minimum is 3.

Example 3:

Input: distance = [1,2,3,4], start = 0, destination = 3
Output: 4
Explanation: Distance between 0 and 3 is 6 or 4, minimum is 4.

  Constraints:

• 1 <= n&nbsp;<= 10^4

• distance.length == n

• 0 <= start, destination < n

• 0 <= distance[i] <= 10^4

Solution (Java)

class Solution {
    public int distanceBetweenBusStops(int[] distance, int start, int destination) {
        if (start > destination) {
            int tmp = start;
            start = destination;
            destination = tmp;
        }
        int clockwise = 0;
        for (int i = start; i < destination; i++) {
            clockwise += distance[i];
        }
        int counterClockwise = 0;
        for (int i = destination; i < distance.length; i++) {
            counterClockwise += distance[i];
        }
        for (int i = 0; i < start; i++) {
            counterClockwise += distance[i];
        }

        return Math.min(clockwise, counterClockwise);
    }
}

Explain:

nope.

Complexity:

• Time complexity : O(n).
• Space complexity : O(n).