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

Q: QRPOwtZATjDoJDdRNNSOH, wiafFMwpAjDoJDdRNNuCDZ

A: jDoJDdRNN
****
Q: jyJrDIhxJtWbnooEXZ, uyXifNCIhxJtWbnVCUrt

A: IhxJtWbn
****
Q: nKhPQDqVWFDWlhR, wCDqVWFFola

A:
DqVWF
****