Longest Contiguous Palindromic Subarray

You are given an array of integers of length \(N\). A contiguous subarray is considered palindromic if it reads the same forwards and backwards.

Your task is to determine the length of the longest contiguous subarray which is a palindrome.

Definition:

A subarray \(A[l \ldots r]\) is palindromic if \(A[l] = A[r], A[l+1] = A[r-1], \dots \). Formally, for \(0 \leq l \leq r < N\), the subarray is palindromic if

[ \forall, 0 \leq i \leq r - l, \quad A[l+i] = A[r-i] ]

Example:

Consider the array: [1, 2, 3, 4, 3, 2, 1]. The entire array is a palindrome so the answer is 7.

inputFormat

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

outputFormat

Output a single integer, which is the length of the longest contiguous palindromic subarray.

## sample

7
1 2 3 4 3 2 1

7