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

[Q]: IIbJjQKWaoGKHGgWPcy, uNoMWaoGKHGqbnjmYQ
[A]: WaoGKHG


[Q]: HaIPcFXLhYDp, AdIPcFXtJdRE
[A]: IPcFX


[Q]: SOBUNu, tbBURX
[A]:
BU