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

[Q]: cZSEmdgP, YsSEmEIM
[A]: SEm


[Q]: XjYkMfARxWBSBjuXyDrFt, EtUxIfiHkMfARxWBSckTLTTnR
[A]: kMfARxWBS


[Q]: IJEMoazArmVul, ZPazArmBpasA
[A]:
azArm