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

[Q]: HqaOvLaZbs, RifOvLaZkh
[A]: OvLaZ

[Q]: jAinxmaQUrmu, jqeEnxmaQUrWlrEqW
[A]: nxmaQUr

[Q]: DBnGdblIdrRGTBs, xVzscprGdblIdrsHO
[A]:
GdblIdr