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

Q: kWTQrtCaoTbXIiXDphMG, pLhxkfeDoTbXIiXDpCCzTYyZv

A: oTbXIiXDp
****
Q: sGrHRmELarByxp, cDCUnmELarBXbEfM

A: mELarB
****
Q: wxzUOzcK, hdZUOzXN

A:
UOz
****