ssss["x:[*map(int,x.split())]"m["s:lambda a,b,c,d,e,f,g,h,i=[s[i+3]-s[i%3]for i in range(9)]:(a*e*i+b*f*g+c*d*h-a*h*f-b*i*d-c*g*e)/6"m0&