Problem:
Score : 200 points

Problem Statement

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.

Constraints

1≤N≤100

The lengths of s and t are both N.

s and t consist of lowercase English letters.

Input

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

N
s
t

Output

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

Sample Input 1

3
abc
cde

Sample Output 1

5

The shortest string is abcde.

Sample Input 2

1
a
z

Sample Output 2

2

The shortest string is az.

Sample Input 3

4
expr
expr

Sample Output 3

4

The shortest string is expr.

Solution in PyPy3 (2.4.0) (judge verdict: Wrong Answer)

N = int(input())
s = input()
t = input()

st = s+t
total_len = len(st)
dupl = 0
for n in range(N+1):
    if st[N-n:N] == st[N:N+n]:
        dupl = len(s[n-n:N])

total_len = total_len - dupl

print(total_len)