c d = 9
c n = 27
c p = 72
c r = 3
p cnf 27 72
17 18 1 0
-17 -18 1 0
17 -18 -1 0
-17 18 -1 0
1 19 2 0
-1 -19 2 0
1 -19 -2 0
-1 19 -2 0
2 20 3 0
-2 -20 3 0
2 -20 -3 0
-2 20 -3 0
3 21 4 0
-3 -21 4 0
3 -21 -4 0
-3 21 -4 0
4 22 5 0
-4 -22 5 0
4 -22 -5 0
-4 22 -5 0
5 23 6 0
-5 -23 6 0
5 -23 -6 0
-5 23 -6 0
6 24 7 0
-6 -24 7 0
6 -24 -7 0
-6 24 -7 0
7 25 8 0
-7 -25 8 0
7 -25 -8 0
-7 25 -8 0
8 26 27 0
-8 -26 27 0
8 -26 -27 0
-8 26 -27 0
9 26 27 0
-9 -26 27 0
9 -26 -27 0
-9 26 -27 0
10 25 9 0
-10 -25 9 0
10 -25 -9 0
-10 25 -9 0
11 24 10 0
-11 -24 10 0
11 -24 -10 0
-11 24 -10 0
12 23 11 0
-12 -23 11 0
12 -23 -11 0
-12 23 -11 0
13 22 12 0
-13 -22 12 0
13 -22 -12 0
-13 22 -12 0
14 21 13 0
-14 -21 13 0
14 -21 -13 0
-14 21 -13 0
15 20 14 0
-15 -20 14 0
15 -20 -14 0
-15 20 -14 0
16 19 15 0
-16 -19 15 0
16 -19 -15 0
-16 19 -15 0
17 18 -16 0
-17 -18 -16 0
17 -18 16 0
-17 18 16 0