Longest Mountain in an Array

You are given an array of positive integers. Your task is to find the length of the longest mountain in the array.

A mountain is defined as a subarray that:

• Has at least 3 elements.
• There exists some index i (0 < i < n-1) such that:
• The elements from the beginning of the mountain to i (inclusive) are strictly increasing.
• The elements from i to the end of the mountain are strictly decreasing.

If no mountain exists in the array, output 0.

Note that the mountain must have a peak and be strictly increasing before and strictly decreasing after the peak.

inputFormat

The first line of input contains a single integer N, the number of elements in the array. The second line contains N space-separated positive integers representing the array.

outputFormat

Output a single integer, the length of the longest mountain in the array. If no mountain exists, output 0.

12
2 1 4 7 3 2 5 5 4 3 2 1

5