import std.stdio;void main(){int[30]a;for(int i;readf(" %d",&a[i]);)a[i]-=a[i%3]*(i++>2);write=(a[11]*(a[7]*a[3]-a[4]*a[6])+a[10]*(a[5]*a[6]-a[3]*a[8])+a[9]*(a[4]*a[8]-a[7]*a[5]))/6;}