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

Q: yJRITYgVTSNsPjG, NSIdKYgVTSNmj

A: YgVTSN
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Q: HqaOvLaZbs, RifOvLaZkh

A: OvLaZ
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Q: XygvTdGCAcHSsPyx, CrrNyasgvTdGCAOca

A:
gvTdGCA
****