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

Q: UiaECWZf, gRyaECWLGRl

A: aECW
****
Q: pqFpUjQGiofBOjfYkRW, pQMnCFlhFpUjQGiofbc

A: FpUjQGiof
****
Q: qvxevsBf, bHevsUn

A:
evs
****