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: FCKbAgSVgj, wAEAWbAgSVSVwD

Answer: bAgSV


Question: fBpRXPkikQokGVeS, FwUbKXkikQokGos

Answer: kikQokG


Question: CLIenGaPKQIqW, sOAnGaPKQIrZ

Answer:
nGaPKQI