DZY Loves Sequences

题意翻译

## 题目描述 给一个长度为n的序列a，定义ai,ai+1,ai+2....aj(1<=i<=j<=n)的长度为j-i+1，你可以最多更改一个数字，求最长的严格递增子段 ## 输入格式 第一行包含n(1<=n<=10^5)表示序列长度。下一行包含a1到an(1<=ai<=10^9) ## 输出格式 输出最长的递增子段的长度 ## 说明 你可以选择a2,a3,a4,a5,a6并且将a4更改为4

题目描述

DZY has a sequence $ a $ , consisting of $ n $ integers. We'll call a sequence $ a_{i},a_{i+1},...,a_{j} $ $ (1<=i<=j<=n) $ a subsegment of the sequence $ a $ . The value $ (j-i+1) $ denotes the length of the subsegment. Your task is to find the longest subsegment of $ a $ , such that it is possible to change at most one number (change one number to any integer you want) from the subsegment to make the subsegment strictly increasing. You only need to output the length of the subsegment you find.

输入输出格式

输入格式

The first line contains integer $ n (1<=n<=10^{5}) $ . The next line contains $ n $ integers $ a_{1},a_{2},...,a_{n} (1<=a_{i}<=10^{9}) $ .

输出格式

In a single line print the answer to the problem — the maximum length of the required subsegment.

输入输出样例

输入样例 #1

6
7 2 3 1 5 6

输出样例 #1

5

说明

You can choose subsegment $ a_{2},a_{3},a_{4},a_{5},a_{6} $ and change its 3rd element (that is $ a_{4} $ ) to 4.