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: HaIPcFXLhYDp, AdIPcFXtJdRE

Answer: IPcFX


Question: oKZCAErEMqzODnkcNqxVdoBOC, yHzRJuSqzODnkcNqxExr

Answer: qzODnkcNqx


Question: cjIgxeknNN, JrhgxeknOE

Answer:
gxekn