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

Q: XZslQqrShfCXRXyHrFVq, BtOQgQqrShfCXRRCRbMvXPM

A: QqrShfCXR
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Q: BICndZkjoSidWivWATvtqsS, FzVWjoSidWivFaQhkRT

A: joSidWiv
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Q: nrIHKzJCdAQzUDRBYpg, JDzJCdAQzUMMYrLcfO

A:
zJCdAQzU
****