You are given two binary strings A and B. Count the left cyclic rotations of B whose bitwise XOR with A is zero in every position.
For a string P=P0P1…PN−1 of length N, rotating P left k times produces the string whose character at position i is P(i+k)modN. The shift amount k is an integer with 0≤k<N, and two shifts with different k count separately even when they produce the same string.