#include <iostream>
#include <string>
using namespace std;

int main() {
	int a,ans;
	string b,c;
	
	cin >> a >> b >> c;
	ans=a*2;
	int i;
	int v=0;
	for(i=0;i<a;i++){
		if(b[i]==c[v]){
			ans--;
			v++;
		} 
	}	
	if(b==c){
		cout << a << endl;
	}else{
		cout << ans << endl;
	}
	return 0;
}
### Prompt

In CPP, your task is to solve the following problem:

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.

Examples

Input

3
abc
cde


Output

5


Input

1
a
z


Output

2


Input

4
expr
expr


Output

4

### Response

```cpp
#include <iostream>
#include <string>
using namespace std;

int main() {
	int a,ans;
	string b,c;
	
	cin >> a >> b >> c;
	ans=a*2;
	int i;
	int v=0;
	for(i=0;i<a;i++){
		if(b[i]==c[v]){
			ans--;
			v++;
		} 
	}	
	if(b==c){
		cout << a << endl;
	}else{
		cout << ans << endl;
	}
	return 0;
}
```