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

Q: CdRbREFMEDTXnEzgn, zHLEMMEDTXnEPH

A: MEDTXnE
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Q: VpJvIZdkzKovjc, BZEizZdkzKYZ

A: ZdkzK
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Q: gxWFxVfYebkClR, xCSLFxVfYebByjwf

A:
FxVfYeb
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