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

Q: mRVieYomZqJXaTDsShCyfPW, ifOAlnptmZqJXaTDsVMqY

A: mZqJXaTDs
****
Q: zbSNNVc, agSNNtOQ

A: SNN
****
Q: AtvpvIfIzmRw, kPvIfImObn

A:
vIfI
****