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

[Q]: njzfcapS, JDzfcYQh
[A]: zfc


[Q]: VRXUhOYfTul, JqZUhOYKq
[A]: UhOY


[Q]: BhhjIbcCDgqGFISzIK, WIcCDgqGMoWbG
[A]:
cCDgqG