6
7
1  -1   0   0   0   0   0 
0   1  -1   0   0   0   0
0   0   1  -1   0   0   0
0   0   0   1  -1   0   0
0   0   0   0   1  -1   0
0   0   0   0   0   1  -1
inequalities

1
7
1 1 1 1 1 1 1
signs

1
7
1 1 1 1 1 1 1
grading