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

Q: yQRDycTycwH, ImycTycrR

A: ycTyc
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Q: JAGuNgaUudP, eojvKNgaUuQg

A: NgaUu
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Q: HVQJDGKRqFJaoFcZGaAIMegho, rwgjQQjRqFJaoFcZGueBAqzCF

A:
RqFJaoFcZG
****