#D5587. Derangement

    ID: 4647 Type: Default 1000ms 536MiB

Derangement

Derangement

G --Derangement / Derangement

Story

Person D is doing research on permutations. At one point, D found a permutation class called "Derangement". "It's cool to have a perfect permutation !!! And it starts with D !!!", the person of D who had a crush on Chunibyo decided to rewrite all the permutations given to him.

Problem

Given a permutation of length n, p = (p_1 p_2 ... p_n). The operation of swapping the i-th element and the j-th element requires the cost of (p_i + p_j) \ times | i-j |. At this time, find the minimum cost required to make p into a perfect permutation using only the above swap operation.

However, the fact that the permutation q is a perfect permutation means that q_i \ neq i holds for 1 \ leq i \ leq n. For example, (5 3 1 2 4) is a perfect permutation, but (3 2 5 4 1) is not a perfect permutation because the fourth number is 4.

Input

The input consists of the following format.

n p_1 p_2 ... p_n

The first row consists of one integer representing the length n of the permutation. The second line consists of n integers, and the i-th integer represents the i-th element of the permutation p. Each is separated by a single blank character.

Constraints:

  • 2 \ leq n \ leq 100
  • 1 \ leq p_i \ leq n, i \ neq j ⇔ p_i \ neq p_j

Output

Print the minimum cost to sort p into a complete permutation on one line. Be sure to start a new line at the end of the line.

Sample Input 1

Five 1 2 3 5 4

Sample Output 1

7

After swapping 1 and 2, swapping 1 and 3 yields (2 3 1 5 4), which is a complete permutation.

Sample Input 2

Five 5 3 1 2 4

Sample Output 2

0

It is a perfect permutation from the beginning.

Sample Input 3

Ten 1 3 4 5 6 2 7 8 9 10

Sample Output 3

38

Example

Input

5 1 2 3 5 4

Output

7

inputFormat

Input

The input consists of the following format.

n p_1 p_2 ... p_n

The first row consists of one integer representing the length n of the permutation. The second line consists of n integers, and the i-th integer represents the i-th element of the permutation p. Each is separated by a single blank character.

Constraints:

  • 2 \ leq n \ leq 100
  • 1 \ leq p_i \ leq n, i \ neq j ⇔ p_i \ neq p_j

outputFormat

Output

Print the minimum cost to sort p into a complete permutation on one line. Be sure to start a new line at the end of the line.

Sample Input 1

Five 1 2 3 5 4

Sample Output 1

7

After swapping 1 and 2, swapping 1 and 3 yields (2 3 1 5 4), which is a complete permutation.

Sample Input 2

Five 5 3 1 2 4

Sample Output 2

0

It is a perfect permutation from the beginning.

Sample Input 3

Ten 1 3 4 5 6 2 7 8 9 10

Sample Output 3

38

Example

Input

5 1 2 3 5 4

Output

7

样例

5
1 2 3 5 4
7