https://codeforces.com/contest/1119/problem/H

Hint: Similar to the official editorial, after shifting \(a_i\) to \(0\), every term of \(H(V)\) is \((x+y+z)^{B_{i,1}}(x+y-z)^{B_{i,2}}(x-y+z)^{B_{i,3}}(x-y-z)^{B_{i,4}}\). However, \(H(\text{cnt}_b)\) and \(H(\text{cnt}_c)\) are not enough to get \(4\) variables, as there are only \(3\) equations. There is \(H(\text{cnt}_{\text{something}})\) which can help.