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

Answer: IHqbEhp


Question: CzkPtkpMTDeNZwCPbJJn, HzpMVDeNZwCPbJVOU

Answer: DeNZwCPbJ


Question: GuxeYAJt, GGxeYQRn

Answer:
xeY