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

Q: aiqZheFuLtXAGRCGNBTAX, ssnVdztXAGRCGNBTIqmSJLZcy

A: tXAGRCGNBT
****
Q: faHRBWyXsYzYmHQyy, aHTyXsYzYeXBFV

A: yXsYzY
****
Q: zVCzUCpBhl, AmzUCpgaX

A:
zUCp
****