2105.给植物浇水II

方法：模拟+双指针

今天是给植物浇水II，昨天是I，本质上和昨天的没有区别，都是模拟，今天额外需要注意的就是需要用一下双指针，其实题目的描述就是双指针了，所以一般情况下都会用到。。。

class Solution {public int minimumRefill(int[] plants, int capacityA, int capacityB) {int len = plants.length;int ans = 0;int waterA = capacityA, waterB = capacityB;for (int i = 0, j = len - 1; i < len && j >= 0 && i <= j; i ++ , j -- ) {if (i == j) {if (waterA >= waterB) {if (waterA >= plants[i]) {waterA -= plants[i];} else {waterA = capacityA;waterA -= plants[i];ans ++ ;}} else {if (waterB >= plants[j]) {waterB -= plants[i];} else {waterB = capacityB;waterB -= plants[i];ans ++ ;}}continue;}if (waterA >= plants[i]) {waterA -= plants[i];} else {waterA = capacityA;waterA -= plants[i];ans ++ ;}if (waterB >= plants[j]) {waterB -= plants[j];} else {waterB = capacityB;waterB -= plants[j];ans ++ ;}}return ans;}
}

时间复杂度：
O(n)

空间复杂度：
O(1)