cube
*objective is derived from
*   0 -1  1  1  1 
*from cube-1.ext.lp
H-representation
begin
6 4 rational
 0  1  0  0 
 0  0  1  0 
 0  0  0  1 
 1 -1  0  0 
 1  0 -1  0 
 1  0  0 -1 
end
minimize -1  1  1  1 
lponly
