Let's swap
91% Success2764 Attempts30 Points2s Time Limit256MB Memory1024 KB Max Code

Y is alone too and has a permutation \(p_1, p_2, ..., p_n\) of numbers from \(1\) to \(n\).

Y thinks that a permutation \(p_1, p_2, ..., p_n\)  beautifulness is defined as value of \(\sum |p_i - i|, 1 \leq i \leq n\).

Y can swap two elements of the permutation at most once, what is the maximum beautifulness that Y can get?

Input

First line contains only \(n\).

Second line contains the permutation \(p_1, p_2, ..., p_n\) separated by space.

\(1 \leq n \leq 10^5\)

\(1 \leq p_i \leq n\), all \(p_i\) are distinct.

Output

The only line of output contains an integer, maximum beautifulness that Y can get.

Examples
Input
5
1 4 2 3 5
Output
12
Explanation

Y can swap \(1\)th and \(5\)th element and the permutation becomes \(5, 4, 2, 3, 1\) with beautifulness \(|5 - 1| + |4 - 2| + |2 - 3| + |3 - 4| + |5 - 1| = 12\).

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