Contest: Task: Related: TaskB

Score : $200$ points

Snuke is interested in strings that satisfy the following conditions:

- The length of the string is at least $N$.
- The first $N$ characters equal to the string $s$.
- The last $N$ characters equal to the string $t$.

Find the length of the shortest string that satisfies the conditions.

- $1≤N≤100$
- The lengths of $s$ and $t$ are both $N$.
- $s$ and $t$ consist of lowercase English letters.

The input is given from Standard Input in the following format:

$N$ $s$ $t$

Print the length of the shortest string that satisfies the conditions.

3 abc cde

5

The shortest string is `abcde`

.

1 a z

2

The shortest string is `az`

.

4 expr expr

4

The shortest string is `expr`

.