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

Q: QRPOwtZATjDoJDdRNNSOH, wiafFMwpAjDoJDdRNNuCDZ

A: jDoJDdRNN
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Q: qQkmYsYN, UhkmYHSy

A: kmY
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Q: zaYPUCzPHNrTMhVaVkXr, XmSnWAzPHNrTMhVaABqqzCgRy

A:
zPHNrTMhVa
****