You want to water nplants in your garden with a watering can. The plants are arranged in a row and are labeled from 0to n - 1from left to right where the ithplant is located at x = i. There is a river at x = -1that you can refill your watering can at.

Each plant needs a specific amount of water. You will water the plants in the following way:

(资料图片仅供参考)

Water the plants in order from left to right.

After watering the current plant, if you do not have enough water to completely water the next plant, return to the river to fully refill the watering can.

You cannot refill the watering can early.

You are initially at the river (i.e., x = -1). 

It takes one step to move one unit on the x-axis.

Given a 0-indexed integer array plantsof nintegers, where plants[i]is the amount of water the ithplant needs, and an integer capacityrepresenting the watering can capacity, return the number of steps needed to water all the plants.

Example 1:

Input: 

plants = [2,2,3,3], capacity = 5

Output: 14

Explanation: 

Start at the river with a full watering can:

- Walk to plant 0 (1 step) and water it. Watering can has 3 units of water. 

- Walk to plant 1 (1 step) and water it. Watering can has 1 unit of water.

- Since you cannot completely water plant 2, walk back to the river to refill (2 steps). 

- Walk to plant 2 (3 steps) and water it. Watering can has 2 units of water. 

- Since you cannot completely water plant 3, walk back to the river to refill (3 steps).

- Walk to plant 3 (4 steps) and water it.Steps needed = 1 + 1 + 2 + 3 + 3 + 4 = 14.

Example 2:

Input: 

plants = [1,1,1,4,2,3], capacity = 4

Output: 30

Explanation: 

Start at the river with a full watering can:

- Water plants 0, 1, and 2 (3 steps).

Return to river (3 steps). 

- Water plant 3 (4 steps). 

Return to river (4 steps). 

- Water plant 4 (5 steps). 

Return to river (5 steps). 

- Water plant 5 (6 steps). 

Steps needed = 3 + 3 + 4 + 4 + 5 + 5 + 6 = 30.

Example 3:

Input: plants = [7,7,7,7,7,7,7], capacity = 8

Output: 49

Explanation: 

You have to refill before watering each plant.Steps needed = 1 + 1 + 2 + 2 + 3 + 3 + 4 + 4 + 5 + 5 + 6 + 6 + 7 = 49.

路是要走完的，所以这个plants的长度是必须要加上去的，剩下的就是要计算每次折弯的路程即可，只要剩下的水，小于下次要浇水的量，则必须折返，所以加上折返的路程即可。

下面是代码：

Constraints:

n == plants.length

1 <= n <= 1000

1 <= plants[i] <= 106

max(plants[i]) <= capacity <= 109

Runtime: 0 ms, faster than 100.00% of Java online submissions for Watering Plants.

Memory Usage: 42.5 MB, less than 24.56% of Java online submissions for Watering Plants.

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