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

SOLUTION: dzqdaG

PROBLEM: ykDpbd, YFDpmO

SOLUTION: Dp

PROBLEM: NDOnTdJhzB, sdbRnTdJhXq

SOLUTION:
nTdJh