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

Q: rvLoiycpZw, idcvoiycpcLyD

A: oiycp
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Q: oKZCAErEMqzODnkcNqxVdoBOC, yHzRJuSqzODnkcNqxExr

A: qzODnkcNqx
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Q: xwJJjpSFmYwkIpfoHFG, htuQjpSFmYwkIxVDYhQgqW

A:
jpSFmYwkI
****