crystal, 105 bytes

Result

WA

Duration

521ms

Code [DL]

a=`dd`.split.map &.to_i;p (0..8).map{|z|z/6*(a[z]-=a[9+z%3])*(a[3+p=-~z%3]*a[q=~-z%3]-a[q+3]*a[p])}.sum/6

stdin

99 91 08
01 84 62
02 52 02
75 45 56

stdout

stderr

Syntax error in /volume/CODE:1: expecting token ']', not '='

a=`dd`.split.map &.to_i;p (0..8).map{|z|z/6*(a[z]-=a[9+z%3])*(a[3+p=-~z%3]*a[q=~-z%3]-a[q+3]*a[p])}.sum/6
                                                                   ^

strace