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: vMsEJRoLkWcmkuwNRz, ZmoLkWcmVZiBv

Answer: oLkWcm


Question: GHdeqnuYnQ, zzQeqnutAZ

Answer: eqnu


Question: dBzTnsdPgTzou, vrtzTnsdPwTJs

Answer:
zTnsdP