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

Q: tWJoKSOAuVhmsomA, emdmnBFJoKSOAuVzSgW

A: JoKSOAuV
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Q: QjDQjzAIsnYgNmmetl, vyqDQjzAIsnNajYEheP

A: DQjzAIsn
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Q: PoFmNbmfxTXmPnETDGDvUE, VgwCOhxTXmPnETDkAFxD

A:
xTXmPnETD
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