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

[Q]: VByrCcgcxCfPGDFqIWGloQZTMQf, OqfPGDFqIWGlalTCCkKkMf
[A]: fPGDFqIWGl


[Q]: zzEhnt, sYEhtc
[A]: Eh


[Q]: RINTFpaOwxDhYJLQHaWHxFf, HpWBhVpaOwxDhYJXon
[A]:
paOwxDhYJ