There are Y lines parallel to x axis. And there are exactly n number of point in each lines. Now wanwan want to move these point in lines which is parallel to y axis. And exactly n lines totaly. And for each point (x,y) , only the value of x can be changed.
And no two point can in the same position. Move a point (x, y) to (x', y) cost abs(x' - x) . Now wanwan want to know the minimum of the total cost to finish the job. 

The first line of the input is an integer T, which means there are exactly T cases in the input.

For each test , the first line contain tow integers Y , n(0<Y ，n< 1000), and follow Y lines , every line contain n integers , the jth integer x[ i ][ j ] represent the x_axis of the jth point in the ith line（abs( x[i][j]) < 1000000 )

For each case, output the minimum of the total cost to finish the job. 

1

3 3

1 2 3

1 3 4

0 1 2

5