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

SOLUTION: hfHvcRouH

PROBLEM: oZNKLmfxecDfkXEGFkRBYk, tReqkiExecDfkXEGtNZpJVRxC

SOLUTION: xecDfkXEG

PROBLEM: OXMPEojVxMIGCoqdkFEoE, iDBcXBxMIGCoqdkFGXStk

SOLUTION:
xMIGCoqdkF