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

SOLUTION: SF

PROBLEM: NUuLSmDjCKcJPc, lGGSLIDjCKcJBo

SOLUTION: DjCKcJ

PROBLEM: opTfpLIwLchTlx, iPIQMIwLchTvFsx

SOLUTION:
IwLchT