c status 20
c --eliminateinit=0
p cnf 10 11
7 6 0
-6 -10 -9 0
-7 1 0
2 -3 0
-2 9 0
4 5 0
10 0
3 -4 0
-6 -5 0
-8 -1 0
-1 8 0