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

Q: UysTOtIRtRorNAFKKYD, icDOtIRtRoropYVaKzJ

A: OtIRtRor
****
Q: jsXHot, gtXHmB

A: XH
****
Q: lordXf, ddrdHv

A:
rd
****