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

[Q]: UovaYpHjYSQzrfsxRfvIZE, pUOFxIKOGQzrfsxRfvIjrza
[A]: QzrfsxRfvI


[Q]: ezVsFayUPcrte, lfsFayUMPTqx
[A]: sFayU


[Q]: XfVrSLTEDa, vbVrSLejK
[A]:
VrSL