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Longest Mountain in Array
Difficulty: Medium
Category: DSA
Topics: Two Pointers
Asked at: Amazon, Paypal
You may recall that an array `arr` is a mountain array if and only if:
`arr.length >= 3`
There exists some index `i` (0-indexed) with `0 arr[i + 1] > ... > arr[arr.length - 1]`
Given an integer array `arr`, return the length of the longest subarray, which is a mountain. Return `0` if there is no mountain subarray.
Example 1:
Input: arr = [2,1,4,7,3,2,5]
Output: 5
Explanation: The largest mountain is [1,4,7,3,2] which has length 5.
Example 2:
Input: arr = [2,2,2]
Output: 0
Explanation: There is no mountain.
Constraints:
`1 <= arr.length <= 104`
`0 <= arr[i] <= 104`
Follow up:
Can you solve it using only one pass?
Can you solve it in `O(1)` space?
Opening the problem
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