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: BmxgSFWBlVX, kGgKrgSFWBlGunFcZ

Answer: gSFWBl


Question: TizkNtJUPHfhmGQ, enzehVkNtJUPHunpG

Answer: kNtJUPH


Question: HuxkNGQGLxKJfcyBhVHt, VUxKJfcyBhVbXyqiV

Answer:
xKJfcyBhV