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

Q: RwqzMTeLMdPx, qaWtYhqzMTeLMdHbWDT

A: qzMTeLMd
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Q: IJQqdzqdaGEIcdyh, izlVdzqdaGGiPYz

A: dzqdaG
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Q: rxRkUTcsVeqvqnkT, GHhiTcsVeqvqnrKBo

A:
TcsVeqvqn
****