### Problem Statement

For a sequence $X$, let $f(X) =$ (the minimum number of elements one must modify to make $X$ a palindrome).

Given a sequence $A$ of length $N$, find the sum of $f(X)$ over all contiguous subarrays of $A$.

Here, a sequence $X$ of length $m$ is said to be a palindrome if and only if the $i$-th and the $(m+1-i)$-th elements of $X$ are equal for all $1 \le i \le m$.

### Input

The input is given from Standard Input in the following format:

```
$N$
$A_1$ $A_2$ $\dots$ $A_N$
```

### Output

Print the answer as an integer.

### Input

The input is given from Standard Input in the following format:

```
$N$
$A_1$ $A_2$ $\dots$ $A_N$
```

9

• f(5)=0
• f(2)=0
• f(1)=0
• f(2)=0
• f(2)=0
• f(5,2)=1
• f(2,1)=1
• f(1,2)=1
• f(2,2)=0
• f(5,2,1)=1
• f(2,1,2)=0
• f(1,2,2)=1
• f(5,2,1,2)=2
• f(2,1,2,2)=1
• f(5,2,1,2,2)=1

Therefore, the sought answer is 9.