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# 1518. Water Bottles

<https://leetcode.com/problems/water-bottles>

## Description

Given `numBottles` full water bottles, you can exchange `numExchange` empty water bottles for one full water bottle.

The operation of drinking a full water bottle turns it into an empty bottle.

Return the **maximum** number of water bottles you can drink.

**Example 1:**

![](https://assets.leetcode.com/uploads/2020/07/01/sample_1_1875.png)

```

**Input:** numBottles = 9, numExchange = 3
**Output:** 13
**Explanation:** You can exchange 3 empty bottles to get 1 full water bottle.
Number of water bottles you can drink: 9 + 3 + 1 = 13.
```

**Example 2:**

![](https://assets.leetcode.com/uploads/2020/07/01/sample_2_1875.png)

```

**Input:** numBottles = 15, numExchange = 4
**Output:** 19
**Explanation:** You can exchange 4 empty bottles to get 1 full water bottle. 
Number of water bottles you can drink: 15 + 3 + 1 = 19.
```

**Example 3:**

```

**Input:** numBottles = 5, numExchange = 5
**Output:** 6
```

**Example 4:**

```

**Input:** numBottles = 2, numExchange = 3
**Output:** 2
```

**Constraints:**

* `1 <= numBottles <= 100`
* `2 <= numExchange <= 100`

## ac

```java
```