环形公交路线上有 n
个站,按次序从 0
到 n - 1
进行编号。我们已知每一对相邻公交站之间的距离,distance[i]
表示编号为 i
的车站和编号为 (i + 1) % n
的车站之间的距离。
环线上的公交车都可以按顺时针和逆时针的方向行驶。
返回乘客从出发点 start
到目的地 destination
之间的最短距离。
示例 1:
输入:distance = [1,2,3,4], start = 0, destination = 1 输出:1 解释:公交站 0 和 1 之间的距离是 1 或 9,最小值是 1。
示例 2:
输入:distance = [1,2,3,4], start = 0, destination = 2 输出:3 解释:公交站 0 和 2 之间的距离是 3 或 7,最小值是 3。
示例 3:
输入:distance = [1,2,3,4], start = 0, destination = 3 输出:4 解释:公交站 0 和 3 之间的距离是 6 或 4,最小值是 4。
提示:
1 <= n <= 10^4
distance.length == n
0 <= start, destination < n
0 <= distance[i] <= 10^4
方法一:一次遍历
class Solution:
def distanceBetweenBusStops(
self, distance: List[int], start: int, destination: int
) -> int:
if start > destination:
start, destination = destination, start
a = sum(distance[start:destination])
b = sum(distance[:start]) + sum(distance[destination:])
return min(a, b)
class Solution {
public int distanceBetweenBusStops(int[] distance, int start, int destination) {
if (start > destination) {
return distanceBetweenBusStops(distance, destination, start);
}
int a = 0, b = 0;
for (int i = 0; i < distance.length; ++i) {
if (i >= start && i < destination) {
a += distance[i];
} else {
b += distance[i];
}
}
return Math.min(a, b);
}
}
class Solution {
public:
int distanceBetweenBusStops(vector<int>& distance, int start, int destination) {
if (start > destination) return distanceBetweenBusStops(distance, destination, start);
int a = 0, b = 0;
for (int i = 0; i < distance.size(); ++i) {
if (i >= start && i < destination)
a += distance[i];
else
b += distance[i];
}
return min(a, b);
}
};
func distanceBetweenBusStops(distance []int, start int, destination int) int {
if start > destination {
return distanceBetweenBusStops(distance, destination, start)
}
a, b := 0, 0
for i, v := range distance {
if i >= start && i < destination {
a += v
} else {
b += v
}
}
if a < b {
return a
}
return b
}
/**
* @param {number[]} distance
* @param {number} start
* @param {number} destination
* @return {number}
*/
var distanceBetweenBusStops = function (distance, start, destination) {
if (start > destination) {
return distanceBetweenBusStops(distance, destination, start);
}
let a = 0;
let b = 0;
for (let i = 0; i < distance.length; ++i) {
if (i >= start && i < destination) {
a += distance[i];
} else {
b += distance[i];
}
}
return Math.min(a, b);
};