p cnf 0 23
1 0
-2 1 0
-3 1 0
-1 3 0
-4 1 0
-1 4 0
-5 2 0
-6 2 0
-7 3 0
-8 3 0
-9 3 0
-3 7 8 9 0
-7 -8 0
-7 -9 0
-8 -9 0
-10 4 0
-11 4 0
-4 10 11 0
-10 -11 0
-6 7 0
-10 -9 0
-2 5 0
6 0