In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.

Input: Consider Input: umXfmRnUgALpFAqBaKfNfo, aOAXWnUgALpFAqBmNpTCdj

Output: nUgALpFAqB


Input: Consider Input: mRVieYomZqJXaTDsShCyfPW, ifOAlnptmZqJXaTDsVMqY

Output: mZqJXaTDs


Input: Consider Input: zBDqHaeFOTHkSeDSHyRVnID, AkQuhbdTHkSeDSHyTQkppI


Output: THkSeDSHy