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

Q: ChKUlYUTQQBjZMZkgEed, lmQQBjZMZkgdEf

A: QQBjZMZkg
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Q: UmYbssMbmsXkKQuzNasLOib, EMqlbmsXkKQuzNcyHrpZXOQW

A: bmsXkKQuzN
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Q: FtrPJYOPadgDzDngZWHVSKmStelEo, KBpVSBgDzDngZWHVZFfZusfkzV

A:
gDzDngZWHV
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