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: zmbmQuyNGOe, mUMEmQuyiuS

Answer: mQuy


Question: ztkWLUJQXxP, fYluOkWLUJKDX

Answer: kWLUJ


Question: FcsLQzDNuiUdmE, qXhKQxyfsLQzDNuiUPzy

Answer:
sLQzDNuiU