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

Q: VRXUhOYfTul, JqZUhOYKq

A: UhOY
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Q: OgWFOfjNYmXVjBBvOdunIc, eGljKGnzFKFOfjNYmXVjdlqsT

A: FOfjNYmXVj
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Q: blHFtYjoo, VpccHFtYMm

A:
HFtY
****