instruction:
In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
question:
HKqfdEvqDuGhWByFlzIEeYh, VVaZfkLCMuGhWByFlzIOZaXbMCA
answer:
uGhWByFlzI


question:
inquDFuJxtBaaFGCaRzO, NYcnWDuDFuJxtBafxZWCUw
answer:
uDFuJxtBa


question:
hqPQpIKlwWwKuxHgWo, mlIZaNjpIKlwWwKuEs
answer:

pIKlwWwKu