instruction:
In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
question:
ljwjMioOwfOltGBaE, TneNGsoOwfOlxnWWW
answer:
oOwfOl


question:
egYXVtCPvWxP, VMOolyVtCPvWjIx
answer:
VtCPvW


question:
OqDmIFbqlbJTSuYOCijIqr, djqlbJTSuYOcOVzViOc
answer:

qlbJTSuYO