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

[Q]: SUgXyznbUQRpiLUTlRb, jlnwLTnbUQRpioUFyJ
[A]: nbUQRpi


[Q]: IQIHqbEhpVuNATp, GIJIHqbEhpzWb
[A]: IHqbEhp


[Q]: rPygCfzmQsq, aKdXgCfzIEED
[A]:
gCfz