det({{u,0,uv,0,0,0,0,0},{1,0,v-1,0,s,0,0,0},{0,x,0,xy,0,0,0,0},{0,1,0,y-1,0,0,1,0},{0,0,0,0,y-1,0,v-1,-1},{0,0,0,0,xy,0,0,0},{0,0,0,0,0,y-1,uv,u},{0,0,0,0,0,xy,0,0}})