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 Python (3.4.3) (judge verdict: Wrong Answer)

n = int(input())
s = list(input())
t = list(input())

ans = 0

if s[-1] in t:
    for i in range(n):
        ans = 0
        if t[i] == s[-1]:
            for j in range(i):
                if s[-1 - j] == t[i - j]:
                    continue
                else:
                    ans = 1
                    break
            if ans == 0:
                print("".join(s + t[i+1:]))
                break
    if ans == 1:
        print("".join(s + t))
else:
    print("".join(s + t))