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

cxYVucnmEQopeWHrPJ, jNnOaYVucnmEQoSE
YVucnmEQo

QRPOwtZATjDoJDdRNNSOH, wiafFMwpAjDoJDdRNNuCDZ
jDoJDdRNN

HCnnkdzTTIezEfQH, LHynkdzTTIOhZh

nkdzTTI