1615 - Matrix

Time Limit : 3 Second

Memory Limit : 128 MB

Submission: 583

Solved: 171

Description
To efficient calculate the multiplication of a sparse matrix is very useful in industrial filed.

Let's consider this problem:

A is an N*N matrix which only contains 0 or 1. And we want to know the result of A*AT.

Formally, we define B = A*AT, A(i,j) is equal to 1 or 0, and we know the number of  1 in matrix A is M

Input
The input contains several test cases. The first line of input contains a integer C indicating the number of the cases.

For each test case, the first line contains two integer N and M.

and each of next M lines contains two integer X and Y, which means A(x,y) is 1.

N <= 100,000 M <= 1000.C <= 10

Output
For each test case, it should have a integer W indicating how many element in Matrix B isn't zero in one line.
sample input
```2
5 3
1 0
2 1
3 3
3 3
0 0
1 0
2 0```
sample output
```3
9```
hint
AT means the Transpose of matrix A, for more details, AT(i,j) = A(j,i).
eg:
if Matrix A is:
1 2 3
4 5 6
7 8 9

then the matrix AT is
1 4 7
2 5 8
3 6 9
source
The 7th(2012) ACM Programming Contest of HUST Problem Setter: Zheng Zhang
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