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

Q: TTagIJmzrOTdnKr, UONmtdHJmzrOTduWo

A: JmzrOTd
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Q: bmZKWkYPqugcvzbHykblPzQLhK, tPUzKqugcvzbHypzk

A: qugcvzbHy
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Q: CMcgCkg, zHJcgCjs

A:
cgC
****