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

SOLUTION: mZqJXaTDs

PROBLEM: DFRoMPNDAzNgtLsEPseOzC, qykyPjDAzNgtLsEPYTsNrJaNK

SOLUTION: DAzNgtLsEP

PROBLEM: nxeguvvBZdouvK, aYlygRguvvBZkEf

SOLUTION:
guvvBZ