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 C (GCC 5.4.1) (judge verdict: Wrong Answer)

#include <stdio.h>
#include <stdlib.h>

int main(void) {
	int i, j, N = 0, ans = 0;
	char s[100];
	char t[100];

	scanf("%d", &N);
	scanf("%s", s);
	scanf("%s", t);
	ans = N * 2;

	if(s==t){
		ans = N;
	}
	for (i = 0; i < N; i++) {
		if (s[i] == t[0]) {
			for (j = 1; j < (N - i + 1); j++) {
				if (j == (N - i)) {
					ans = N + i;
					break;
				} else if (s[i + j] != t[j]) {
					break;
				}
			}
		}
	}

	printf("%d", ans);

	return 0;
}