Once upon a time, a problem statement was placed before ydc, but he did not cherish it, and only regretted it when it was lost.

If heaven gave him another chance, ydc would definitely remember this problem statement firmly.

Alas, it is already lost, so you must help ydc solve this problem.

The only known information is that this is a traditional problem, using full-text comparison.

ydc has also provided you with all the data for this problem (see the provided files).

The score displayed during the contest is the final score.