Problem Background

$sans$ went to the Monster Academy to steal some questions again, and then handed them over to $Gaster$. $Gaster$ hopes you can help him.

Problem Description

Given a sequence of length $n$, please find the longest contiguous subsequence where the difference between the maximum and minimum numbers in this subsequence is not greater than 1. This subsequence is called a "01 difference" subsequence.

Ensure that the data meets the condition $|a_{i+1} - a_{i}| \le 1$, meaning the difference between any two adjacent numbers is less than or equal to 1.

Input Format

The first line contains an integer $n$ $(2\le n\le 10^5)$ — the size of the sequence.

The second line contains $n$ integers $a_1, a_2, \dots, a_n$ $(1\le a_i \le 100000)$.

Output Format

The length of the longest "01" subsequence.

Examples

Input Example 1

5
1 2 3 3 2

Output Example 1

4

The longest "01" subsequence is [2, 3, 3, 2]. It has a length of 4.

Input Example 2

8
1 2 1 2 1 2 3 2

Output Example 2

6

The longest "01" subsequence is [1, 2, 1, 2, 1, 2]. It has a length of 6.