1184-DistanceBetweenBusStops.go

package main

// 1184. Distance Between Bus Stops
// 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:
// <img src="https://assets.leetcode.com/uploads/2019/09/03/untitled-diagram-1.jpg" />
// 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:
// <img src="https://assets.leetcode.com/uploads/2019/09/03/untitled-diagram-1-1.jpg" />
// 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:
// <img src="https://assets.leetcode.com/uploads/2019/09/03/untitled-diagram-1-2.jpg" />
// 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 <= 10^4
//     distance.length == n
//     0 <= start, destination < n
//     0 <= distance[i] <= 10^4

import "fmt"

func distanceBetweenBusStops(distance []int, start int, destination int) int {
    sum, t := 0, 0
    if start < destination {
        destination, start = start, destination
    }
    for _, v := range distance {
        sum += v
    }
    for i := destination; i < start; i++ {
        t += distance[i]
    }
    min := func (x, y int) int { if x < y { return x; }; return y; }
    return min(t, sum - t)
}

func main() {
    // Example 1:
    // <img src="https://assets.leetcode.com/uploads/2019/09/03/untitled-diagram-1.jpg" />
    // 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.
    fmt.Println(distanceBetweenBusStops([]int{1,2,3,4}, 0, 1)) // 1
    // Example 2:
    // <img src="https://assets.leetcode.com/uploads/2019/09/03/untitled-diagram-1-1.jpg" />
    // 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.
    fmt.Println(distanceBetweenBusStops([]int{1,2,3,4}, 0, 2)) // 3
    // Example 3:
    // <img src="https://assets.leetcode.com/uploads/2019/09/03/untitled-diagram-1-2.jpg" />
    // 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.
    fmt.Println(distanceBetweenBusStops([]int{1,2,3,4}, 0, 3)) // 4
}