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

SOLUTION: JMpx

PROBLEM: DwkTGsIXLfmjMV, VqRlMxtsSBkTGsIXLfmjbvI

SOLUTION: kTGsIXLfmj

PROBLEM: pFgNWZjgTdWYwhz, HmmgNWZjgTdWMHxkDF

SOLUTION:
gNWZjgTdW