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

Answer: aECW


Question: inquDFuJxtBaaFGCaRzO, NYcnWDuDFuJxtBafxZWCUw

Answer: uDFuJxtBa


Question: cZVbIkbmVZAhFffrx, TSkSaUkbmVZAhXahB

Answer:
kbmVZAh