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

Q: BmxgSFWBlVX, kGgKrgSFWBlGunFcZ

A: gSFWBl
****
Q: DQBpdnwVDcnCDEWpD, gAtCdnwVDcnCYv

A: dnwVDcnC
****
Q: HqYCCTdjBhDcErFiZcyEK, CtYijBhDcErzeuJtO

A:
jBhDcEr
****