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

SOLUTION: GrqcrOBgG

PROBLEM: yJRITYgVTSNsPjG, NSIdKYgVTSNmj

SOLUTION: YgVTSN

PROBLEM: XIlqWSTAWT, rAeblqWSTtbPo

SOLUTION:
lqWST