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: iupYjFXrrMqWzJSLUSwmEukHc, hqajjWrrMqWzJSLnF

Answer: rrMqWzJSL


Question: tmBlKUto, eFDBlKLy

Answer: BlK


Question: boYwqimLKhuUDFDNQtCi, MyAiGkjKhuUDFDNXRbwrNB

Answer:
KhuUDFDN