#P7504. [2017年杭电多校]Destroy the cube

[2017年杭电多校]Destroy the cube

Destroy the cube

Problem Description

There is a chessboard with nn rows and nn columns, every position is black or white. It is defined that c(x,y)c(x,y) means the color of the position in the xxth row and the yyth column, and it is guaranteed that c(x,y)=c(y,x)=c(x,ny+1)=c(nx+1,y)c(x,y)=c(y,x)=c(x,n-y+1)=c(n-x+1,y) for any 1x,yn1\leq x,y\leq n, which shows it is quite symmetry. Also because of this, only the colors of the positions (x,y)(x,y) which satisfies xyn+12x\leq y\leq\lfloor\frac{n+1}{2}\rfloor are given, and the number of the given black position is tt in total. Now HazelFan has a big cube with nn layers and nn rows and nn lines, and its six sides are all same as the chessboard. For the three pairs of opposite sides, for each black position on one side, he will dig through the cube from the position straight to a black position on the other side. Please tell him after he destroys the cube, how many little cubes are left.

Input

The first line contains a positive integer T(1T5)T(1\leq T\leq5), denoting the number of test cases. For each test case: The first line contains two positive integers $n,t(1\leq n\leq6\times10^4,1\leq t\leq1.2\times10^5)$. The next tt lines, each line contains two positive integers x,y(1xyn+12)x,y(1\leq x\leq y\leq\lfloor\frac{n+1}{2}\rfloor), denoting a given black position.

Output

For each test case: A single line contains a nonnegative integer, denoting the answer.

Sample Input

2

3 1

2 2

5 2

2 3

3 3

Sample Output

20

76

Source

2017 Multi-University Training Contest - Team 7

https://acm.hdu.edu.cn/showproblem.php?pid=6123