Sum of neighbors

In a square area of size $n\times n$, cells are numbered sequentially from $0$ to $(n^2-1)$ from the top row to the bottom, from left to right in each row.

Nyasyr stands in the cell with number $k$ in this area and wants to find the sum of the numbers of all neighboring cells. Help Nyasyr with this task.

Note that each cell can have no more than $4$ neighbors directly above, below, to the left, and to the right.

Below is an example with $n=4$ and $k=11$.

Here Nyasyr stands on the cell with number $11$, and neighboring cells are marked with circles. In this case, there is no neighbor on the right.

Input

Two integers $n(1\le n\le 10^6)$ and $k(0\le k\le n^2)$.

Output

Print the sum of the numbers of all neighboring cells of the given cell.

Examples