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# 1095. Find in Mountain Array

<https://leetcode.com/problems/find-in-mountain-array>

## Description

*(This problem is an **interactive problem**.)*

You may recall that an array `A` is a *mountain array* if and only if:

* `A.length >= 3`
* There exists some `i` with `0 < i < A.length - 1` such that:
  * `A[0] < A[1] < ... A[i-1] < A[i]`
  * `A[i] > A[i+1] > ... > A[A.length - 1]`

Given a mountain array `mountainArr`, return the **minimum** `index` such that `mountainArr.get(index) == target`.  If such an `index` doesn't exist, return `-1`.

**You can't access the mountain array directly.**  You may only access the array using a `MountainArray` interface:

* `MountainArray.get(k)` returns the element of the array at index `k` (0-indexed).
* `MountainArray.length()` returns the length of the array.

Submissions making more than `100` calls to `MountainArray.get` will be judged *Wrong Answer*.  Also, any solutions that attempt to circumvent the judge will result in disqualification.

**Example 1:**

```
**Input:** array = [1,2,3,4,5,3,1], target = 3
**Output:** 2
**Explanation:** 3 exists in the array, at index=2 and index=5. Return the minimum index, which is 2.
```

**Example 2:**

```
**Input:** array = [0,1,2,4,2,1], target = 3
**Output:** -1
**Explanation:** 3 does not exist in the array, so we return -1.
```

**Constraints:**

* `3 <= mountain_arr.length() <= 10000`
* `0 <= target <= 10^9`
* `0 <= mountain_arr.get(index) <= 10^9`

## ac

```java
```