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

SOLUTION: vlV

PROBLEM: mjCEUoPmeKbvCgUtUL, SrHtrPmeKbvYpQAVp

SOLUTION: PmeKbv

PROBLEM: vmLOJBHigZMxEoCsnT, wQokHigZMxEKUuldw

SOLUTION:
HigZMxE