instruction:
In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
question:
jXqEDHTCxTiUAICWZJdpmYq, GBTCxTiUAICZKnLgZBXi
answer:
TCxTiUAIC


question:
qczzCr, zDzzUI
answer:
zz


question:
GbAFDwckfRAhg, ANswckfRYCd
answer:

wckfR