98. Longest Mountain in Array

Given an integer array arr, return the length of the longest subarray that forms a mountain. A mountain subarray has strictly increasing then strictly decreasing elements, with at least 3 elements. If no mountain exists, return 0.

Input: Integer array arr.

Output: Integer — length of longest mountain subarray, or 0.

Examples

Input: [2,1,4,7,3,2,5]
Output: 5
Explanation: [1,4,7,3,2] has length 5 and is a mountain.

Input: [2,2,2]
Output: 0
Explanation: No mountain — no strictly increasing then decreasing.

Input: [0,1,0]
Output: 3
Explanation: [0,1,0] is the whole array, a mountain of length 3.

Constraints

• 1<=arr.length<=10^4
• 0<=arr[i]<=10^4

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