You are given strings $S$ and $T$ of length $N$ consisting of lowercase English letters. You can repeat the following operation any number of times (possibly zero). - Erase the **first** character of $S$ and insert the same character at any position of $S$. Determine whether it is possible to make $S$ equal $T$, and if it is possible, find the minimum number of operations needed.

The input is given from Standard Input in the following format: >$N$ $S$ $T$ #### Constraints - $1 \le N \le 2 \times 10^5$ - $S$ and $T$ are strings of length $N$ consisting of lowercase English letters.

If it is impossible to make $S$ equal $T$, print `-1`. If it is possible, print the minimum number of operations needed.