Little Fabijan got bored with picture books, so he decided to read his first
fairytale. Unfortunately, Fabijan often encounters a word that scares him. To
overcome his fear, he will play a game he invented.
The scary word can be represented as an array of \(n\) lowercase letters. To start the
game, Fabijan puts his finger on some position of the array and writes the letter
from that position on a piece of paper. He then performs one of the following
moves an arbitrary number of times:
• He moves the finger to a position that is one place to the left or to the right of the current position,
if that position exists. Also, Fabijan will then write the letter from the new position on the paper,
after the last written letter.
• He moves the finger to any position with the same letter as the current one. Fabijan will not write
anyhing on the paper in this case.
It takes him |\(x - y\)| seconds to move the finger from position \(x\) to position \(y\).
Fabijan will overcome his fear of the word if, at the end of the game, his favourite word is written on
the paper. He wants to finish the fairytale as soon as possible, so he asks you to tell him the minimum
number of seconds it will take him to overcome his fear of the given scary word.

In test cases worth 20 points, letters in the word that scares Fabijan will be pairwise distinct.

The first line contains integers \(n\) and \(m\) (\(1 \le n\), \(m \le 300\)).
The second line contains \(n\) lowercase letters, the word that scares Fabijan.
The third line contains \(m\) lowercase letters, Fabijan’s favourite word.

Print the shortest possible time in seconds Fabijan needs to write his favourite word on the paper, \(or - 1\)
if that is not possible.

생성자가 기록되지 않았습니다.

출처 COCI 2020/2021 Contest 1