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

Q: DQBpdnwVDcnCDEWpD, gAtCdnwVDcnCYv

A: dnwVDcnC
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Q: QeNePjbLBKbDOuAVTJtXL, xjPVOyPbLBKbDOuDsMSEF

A: bLBKbDOu
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Q: FFLQeJfdNjwhNUAt, ORPNenLQeJfdNjwRbFQbhBf

A:
LQeJfdNjw
****