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

oGaGjsaKsUpLQAg, iDGjsaKsUoYGuta
GjsaKsU

HiEuutntEBpU, fdkqEuutntEBABdGZRND
EuutntEB

mtWNBOmpDkUDdYVfyyd, pIpmrDkUDdYVfWoyX

DkUDdYVf