In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.

Q: yywhNdZQkLSzbOvhluicHA, lfZQkLSzbOvhVC

A: ZQkLSzbOvh
****
Q: yKtQOhYvrJVH, HQsTQOhYvPP

A: QOhYv
****
Q: hBJVMqbwpE, pTIjMqbwHH

A:
Mqbw
****