TASK DEFINITION: In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
PROBLEM: XZslQqrShfCXRXyHrFVq, BtOQgQqrShfCXRRCRbMvXPM

SOLUTION: QqrShfCXR

PROBLEM: nhGinCtvLartcMPhJwGRbpZNrq, iQJlFKayEartcMPhJwDRROB

SOLUTION: artcMPhJw

PROBLEM: rHxWpz, nSxWsM

SOLUTION:
xW