a={} for i=-3,8 do a[i]=io.read("*n")-a[i%3-3]end
for i=0,2 do b=(i+1)%3 c=(i+2)%3 d=a[i]+a[b+3]+a[c+6] e=a[i]+a[c+3]+a[b+6]end
print(d-e)