g1001_1100.s1095_find_in_mountain_array.readme.md Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of leetcode-in-java Show documentation
Show all versions of leetcode-in-java Show documentation
Java-based LeetCode algorithm problem solutions, regularly updated
1095\. Find in Mountain Array
Hard
_(This problem is an **interactive problem**.)_
You may recall that an array `arr` is a **mountain array** if and only if:
* `arr.length >= 3`
* There exists some `i` with `0 < i < arr.length - 1` such that:
* `arr[0] < arr[1] < ... < arr[i - 1] < arr[i]`
* `arr[i] > arr[i + 1] > ... > arr[arr.length - 1]`
Given a mountain array `mountainArr`, return the **minimum** `index` such that `mountainArr.get(index) == target`. If such an `index` does not exist, return `-1`.
**You cannot 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() <= 104
* 0 <= target <= 109
* 0 <= mountain_arr.get(index) <= 109